Emmenanthe penduliflora (Whispering bells) Equisetum telmateia (Giant horsetail) Crossosoma californicum (Catalina crossosoma)




Although the focus of this website is primarily on California plants, many if not most of these names are in general use world-wide. Therefore some general discussion of botanical nomenclature is relevant and might prove useful. The binomial system of nomenclature pioneered by the great Swedish naturalist Carl Linnaeus (1707-1778) is recognized by botanists everywhere, and consists in the main of generic names derived principally from Greek and specific names derived principally from Latin. These form the two basic parts of scientific names that are applied to all living things. For our purposes, we will ignore the fact that in addition to these two names, there are often names for subspecies and geographic or other variants and also for horticulturally-produced cultivars.

Rules of nomenclature are established by International Botanical Congresses which are held every six years. The first edition of the Jepson Manual was published at about the same time (1993) as the Tokyo Congress and thus does not always reflect recommendations and changes made by that Congress. The St. Louis Code was adopted by the 16th International Botanical Congress in 1999, and more recently the 17th IBC was held in 2005 in Vienna, Austria. The 18th IBC was held in Melbourne, Australia, and this congress adopted the Code which is currently in effect.

The generic names are generally nouns which are capitalized and which define the genus, and the specific names are generally adjectives which are not capitalized and which define or describe the species. Not all species names are descriptive however, since they are sometimes taken from the name of a person or a geographic locality. Just as a species is one of a group of organisms that share a certain characteristic or suite of characteristics that has been decided by taxonomists to be sufficiently significant for that group to be considered a genus, so is a genus one of a group that shares certain characteristics and makes up a family. Species, genus, and family are the three most significant taxa that most people interested in botany seek to know and try to remember.

Botanical Latin is not classical Latin. It is the Latin that derives from the Roman writers of the early first millenium and remained the single internationally used language of learning throughout Europe until at least the 18th century. Were this not the case, there might well be no uniform international system of botanical nomenclature today. Herbalists of the 16th century established the tradition subsequently taken up by Linnaeus that plants should be given Latin names. If there had been no common knowledge and usage of Latin, the vernacularly-written works of local botanists would have been unknown outside their own region. Linnaeus' work reflected the fact that a huge advance had been made in the knowledge of the complexities of structure and relationship of plants, and language had to expand accordingly. Botanical Latin has as a result grown far beyond its original form with the inclusion of vast numbers of new words describing things that were essentially unknown in the ancient world. Stearn makes the point that Pliny (about whom more below) would have well understood the Latin descriptions of plants in the 15th and 16th centuries, but would have been lost by the divergent Latin of the 18th and 19th centuries. Proof of the giant leap in knowledge from the time of the ancients to the present day can be found in the fact that the early botanists like Theophrastus in the third century B.C. described about 500 plants, Pliny three centuries later described about 1000, herbalists of the 15th and 16th centuries perhaps 4000, Linnaeus in the 18th century around 7300, and modern botanists some 250,000 to 300,000 species of flowering plants.

There is therefore little need to utilize strictly classical Latin pronunciation. Over the years, usage has resulted in certain informal rules of pronunciation, but even these must give way to a person's own preferences, and are naturally influenced by such things as where he or she grew up, and what pronunciations they were exposed to during their lifetimes. It may seem simplistic, but what sounds right is often the best standard by which to decide how to pronounce botanical names. However, consistency of pronunciation is to be strived for, and the person who finds himself speaking such names aloud usually does develop a fairly uniform style. The Jepson Manual emphasizes the following points: (1) classical scholars don't always agree on pronunciation; (2) professional botanists vary significantly in their pronunciation; (3) individual botanists rarely are completely consistent in pronunciation; and (4) people tend to pronounce names the way they first learned them regardless of any subsequently-encountered rules.

There are a few guidelines that may be helpful to those learning to pronounce the names I have included in this website. One should try to divide the names into separate syllables on the presumption that each vowel is a different syllable, and try to pronounce each and every syllable. This is not always the case because there are combinations of two vowels (called dipthongs) that form a single sound. In two-syllable words, there is no problem because the accent always falls on the first syllable (MI-nor or AS-per). According to the traditional English system of pronunciation, for words of more than two syllables, the accent is customarily on the penultimate syllable where it contains a long vowel (vul-GAR-is or in-de-COR-um). Where that penultimate syllable consists of a short vowel the accent can fall either on that syllable or on the syllable preceding it (EL-e-gans or Di-TAX-is). Although in names of many syllables there can be a secondary stress toward the beginning, the primary stress is never on a syllable before the antepenultimate one. I have often heard Oligomeris pronounced (and have sometimes pronounced it that way myself) as 'ol-i-go-MER-is,' whereas according to the above-stated guidelines it could as well be pronounced 'ol-i-GO-mer-is,' and similarly although many people may say 'cal-y-co-SER-is, it could just as well be 'cal-y-CO-ser-is.' Yet another difficulty is whether to pronounce 'ch' like 'church' or 'chameleon,' as in names such as Eremalche or Callitriche. There are no doubt many other examples that I can't think of offhand.

A rule that Jepson proposes that I find myself in general agreement with is to retain the pronunciation of proper names when they are incorporated into a botanical name. Sometimes this may be relatively simple, as in hallii or jonesii, but is frequently cumbersome as in the case of Krascheninnikovia or other names where the emphasis is on the first syllable of multi-syllable names such as peirsoniana or eatonii or johnstonii. However, as a convention, it is preferable to retain the proper name's pronunciation when it can be done in a graceful manner, but there is no absolute right or wrong.

In the nomenclatural system that has developed, there is normally agreement between the genders of the specific and generic names, but this is not always the case. What many people are not aware of is that there are three genders that a given Latin name may belong to, masculine, feminine and neuter. Generic names with an -us ending (Malacothamnus, Rhamnus) are almost always masculine, although Pinus and Quercus are two notable feminine exceptions, and there are quite a few other tree names that do not accord with this rule (Juniperus, Prunus, Laurus, Alnus). Names with an -a (Jojoba, Amorpha) ending are generally feminine, unless they are derived from neuter Greek words ending in -ma (Malosma, Adenostoma), and such words include derma, sperma, nema, phragma, stema, and stigma. Names ending in -um (Chenopodium, Eriogonum) are neuter. Names ending in -es (Aphanes, Heteromeles), -e (Agave, Hydrocotyle), -ea (Centaurea, Proboscidea), -ago (Plantago, Solidago), -odes (Sarcodes), -oides (Nymphoides), -ix (Malacothrix, Salix), -ex (Rumex, Atriplex), -ia (Umbellularia, Vicia), -oa (Poa, Salpichroa) or -is (Arabis, Pteris, Agoseris) are feminine, with some exceptions such as the masculine Cucumis. The generic endings -pogon (Tragopogon, Andropogon) and -stemon (Petalostemon, Platystemon) derive from Greek and are masculine. Although the generic name ending -on (Acroptilon, Erigeron) is masculine, names ending in -dendron (Phoradendron, Toxicodendron) are neuter. Names ending in -daphne and -mecon (Stylomecon, Dendromecon) are Greek and feminine. There are many other endings that I am still puzzling over, such as -os (Symphoricarpos is masculine but Arctostaphylos is feminine) and -ax (Styrax is masculine while Smilax is feminine), -ans (Juglans) which judging by the specific epithets it takes is probably feminine, and -io (Senecio), masculine I think. The -ys generic name ending is a puzzle, with again (judging by the specific epithets that go with them), Plagiobothrys appearing to be masculine, and Stachys appearing to be feminine.

Specific epithets must therefore be in accord with the gender of the genus, thus it is Chenopodium album (not alba or albus), Hirschfeldia incana (not incanum or incanus), and Caulanthus heterophyllus (not heterophylla or heterophyllum). There are also specific names for which the masculine and feminine forms are the same, but the neuter form is different, thus masculine and feminine acaulis and neuter acaule, and masculine and feminine campestris and neuter campestre. And finally there are specific names for which the form is the same for all three genders, such as (Lupinus) bicolor and (Trifolium) repens. Specific epithets named for geographic localities typically take the endings -ensis, -(a)nus, -inus, -icus or -ianus. Such geographical epithets are often suspect because they infer a locational source or derivation for a plant which the namer may have been incorrect about. Specific names honoring people follow a few general rules, such as adding -i to a name ending in 'r' or a vowel other than 'a' (palmeri, covillei), adding an -e to names ending in 'a' (magdalenae), and adding -ii (masculine) or -iae (feminine) to names ending with a consonant other than 'r' (eatonii or traskiae). Lastly, -iana is a fairly common honorific name ending, which I believe is feminine (knappiana, abramsiana). Some names were applied with some whimsical or humorous intent, such as Muilla as an anagram of Allium. And some names were just made up out of whole cloth and have no other derivation. A final note with regard to the use of the -i or -ii ending is that the 1993 Tokyo International Code of Botanical Nomenclature (ICBN) has recommended the use of -i for all specific epithets based on "classical" names, thus wislizeni instead of wislizenii and maximiliani instead of maximilianii.

Incidentally, families, which are not part of this binomial system of nomenclature, but are nonetheless taxonomically very significant as the units which includes groups of genera, have their names formed by adding the suffix -aceae to a stem word that is usually the name of a genus in that family. The ending -aceae means "belonging to, or having the form of." Thus the family Hydrophyllaceae is named after its included genus Hydrophyllum, the family Brassicaceae after Brassica, the Iridaceae after Iris, the Liliaceae after Lilium, the Poaceae after Poa, and so on. There are a few examples of family names that do not correspond to this practice, the Compositae, now more typically called the Asteraceae or sunflower family, the Umbelliferae, now called Apiaceae, the carrot family, the Cruciferae, now Brassicaceae or mustard family, the Labiatae, now the Lamiaceae or mint family, the Leguminosae, now called the Fabaceae or pea family, and a few others. These older names have not died out, but they are being supplanted increasingly by the newer ones.

The following paragraphs are quoted from the Jepson Globe, a newsletter published by the Friends of the Jepson Herbarium, as reprinted in The New Mexico Botanist, Issue Number 7, February 18, 1998, and I include them here because they include valuable information about epithets that commemorate specific individuals.

"Grammatically, there are two kinds of commemorative epithets, substantival and adjectival. A substantival commemorative epithet is a noun in the genitive (possessive) case. The inflection (ending) of the epithet varies according to the sex and number of the person(s) being commemorated. Personal names that end in a consonant (except y, which in final position functions as a vowel) can be converted to substantival epithets by the interpolation of -i plus the genitive ending appropriate to the sex and number of the person(s), i.e., -i for a man, -ae for a woman, -arum for two or more women, and -orum for two or more men or persons with both sexes represented. Thus, Chaenactis parishii (Samuel Parish), Lasthenia ferrisiae (Roxana Ferris), and Ceanothus hearstiorum (the Hearst family). Personal names that end in -er are a curious exception among those ending in a consonant in that they do not take the interpolated i. Thus, Phacelia breweri [rather than brewerii] (William Brewer), Horkelia wilderae [rather than wilderiae] (Mrs. H.E. Wilder), and Cordia wagnerorum [rather than wagneriorum] (Dr. and Mrs. Richard J. Wagner).

"Personal names that end in -e, -i, -o, -u, or -y also can be converted to substantival commemorative epithets by the addition of the appropriate genitive inflection (-i, -ae, -arum, or -orum) without interpolating an i. Thus, Eryngium constancei (Lincoln Constance), Eriastrum brandegeeae (Katherine Brandegee), Downingia bacigalupii (Rimo Bacigalupi), Astragalus serenoi (Sereno Watson), Carex rousseaui (Jacques Rousseau), Polystachya moreauae (Mrs. R.E. Moreau), Delphinium parryi (Charles Parry), and Linanthus parryae (Mrs. Charles Parry). Personal names that end in -a are a special case: like other names ending in a vowel, they do not take the interpolated i, but the genitive inflection is limited to -e (singular) or -rum (plural) regardless of sex. Thus Aster greatae, which commemorates Louis Greata, would be equally correct for Mrs. Greata, while greatarum would commemorate both persons. [Anyone reading this carefully may note what appears to me to be an error. The previous paragraph states that -arum is to be used for two or more women, and -orum for two or more men or two or more persons with both sexes represented. Thus the use of greatarum would not seem to be appropriate for Mr. and Mrs. Louis Greata.]

"An adjectival commemorative epithet is a noun converted to an adjective by the addition of a suffix (-an), which is inflected in accordance with the gender of the generic name (-anus, -ana, -anum) but is not affected by the sex or number of the person(s) being commemorated. Personal names ending in a consonant, including those that end in -er, require an interpolated i preceding the suffix. Thus, Bromus orcuttianus (Charles Orcutt), Iris douglasiana (David Douglas), Eriogonum eastwoodianum (Alice Eastwood), and Astragalus jaegerianus (Edmund jaeger). Personal names ending in -e, -i, -o, -u, and -y take the suffix without the interpolated i. Thus, Pogogyne clareana (Clare Hardham), Eriogonum covilleanum (Frederick Coville), Sphaeralcea munroana ("Mr. Munro"), and Clarkia dudleyana (William Dudley). Personal names that end in -a are a special case: like other names ending in a vowel, they do not take the interpolated i, but the suffix is reduced to -nus, -na, or -num. Thus, we have Astragalus claranus (Clara Hunt), and not A. clarianus as originally spelled by Jepson.

"It should be emphasized that the orthography [correct spelling] of substantival commemorative epithets depends solely on the sex and number of the person(s) being commemorated, while the orthography of adjectival commemorative epithets depends solely on the gender of the generic name in which the epithet is used. Thus, we have Mimulus bolanderi, Madia bolanderi, and Trifolium bolanderi (Henry Bolander) compared with Lotus nuttallianus, Puccinellia nuttalliana, and Delphinium nuttallianum (Thomas Nuttall), when used with masculine, feminine and neuter generic names, respectively.

"In the Jepson Manual, substantival commemorative epithets, when translated, are correctly translated as a possessive, such as Bolander's clover. Adjectival commemora-tive epithets, when translated, are translated in the same manner. A more literal, but rarely used translation would be, for example, Nuttallian lotus and Eastwoodian buckwheat. Substantival commemorative names are much more common than adjectival commemorative names."

To sum up the assignment of epithets commemorating people, I quote the following from David Gledhill's The Names of Plants:

To names ending with a vowel (except -a) or -er is added
when masculine singular
when feminine singular
when masculine plural
when feminine plural

To names ending with -a is added


when singular
when plural

To names ending with a consonant (except -er) is added
when masculine singular
when feminine singular
when masculine plural
when feminine plural

To names ending with a vowel (excep -a) is added

when masculine
when feminine
when neuter

To names ending with -a is added

when masculine
when feminine
when neuter

To names ending with a consonant is added

when masculine
when feminine
when neuter

I should mention a brief word about three botanists of classical times who recorded names in general use for the plants that were familiar to them. Theophrastus (c. 371-287 B.C.) was a Greek philosopher from Lesbos who studied under both Plato and Aristotle, and succeeded the latter for some thirty-five years as the head of the Lyceum, the academy in Athens that Aristotle founded. He wrote the nine-volume Peri phyton historia, "An Inquiry Into Plants," and the six-volume Peri phyton aition, "On Growth of Plants." He continued Arisotle's procedure of questioning and criticism, and introduced the principle that the conclusion cannot be stronger than the weakest premise. His work called the Historia Plantarum established his position in some people's eyes as the Father of Botany.

Several hundred years after Theophrastus' time, the Greek physician Pedanius Dio-scorides (c. 40-90 A.D.) was perhaps one of the first to belong to that botanical tradition of coming to botany through a medical background. He was a military surgeon under the Roman Emperor Nero, and travelled through the ancient world of Italy, Gaul, Spain and North Africa, observing and recording information about the medicinal value of plants. His work, written around 70 A.D. in Greek and later translated into Latin as De Materia Medica, was considered the authority on medicinal plants for 1,500 years, and has been called "the most successful botanical textbook ever written." A copy of this work from around 512 A.D. is kept at the Austrian National Library in Vienna and is the oldest and most valuable manuscript in the history of botany.

A contemporary of Dioscorides was Gaius Plinius Secundus, known more familiarly as Pliny the Elder (23-79 A.D.), a Roman naturalist, encyclopedist and writer whose 37-volume Naturalis historia included 15 volumes on plants. He recorded the Latin synonyms of Greek plant names, and thereby made most of the plants recorded in earlier Greek writings identifiable. A novel feature of the Natural History was Pliny's careful listing of his sources, of which more than 100 are mentioned. Toward the end of his life, Pliny was a Roman Senator and the commander of the fleet at Misenum in the Bay of Naples, and when Mt. Vesuvius erupted in 79 A.D. he determined to learn more about it and tried unsuccessfully to land at Pompeii with ash and volcanic rocks falling on his ship. He sailed a few miles further south and was able to go ashore at Stabiae to comfort the frightened citizens and effect rescues if possible. It seems that he was not fully aware of the potential hazards, and before he was able to launch his ships to depart was overcome by the poisonous volcanic fumes and died on August 24.

These three men were the great ones of early botany, but there were no doubt many others who labored in obscurity and whose efforts did not survive the long period until medieval times when herbalists once again began to study plants. However, it is also due to the many people whose names have been lost and who tirelessly hand-copied the works of these three giants century after century that the modern world has inherited the knowledge that they spent their lives acquiring. One can only wonder what botanical works of our times, if any, will still be in existence a thousand years hence.

One last point that people should recognize is that the identification of plants is an on-going process, and that plant taxonomy is neither absolute nor fixed, but merely reflects the current state of our knowledge. The ancients attempted to relate types of plants based on what were then the most visible and obvious characteristics. Without microscopes, the smaller features of plant physiology were unknown to them. As our ability to discern smaller and smaller structures has increased, naturally we can get a better idea of what plants are related to what other plants. But the advent of the electron microscope and even more the rise of genetic analysis will no doubt show us many new things and cause many plant relationships to be altered. It is indeed ironic that we are facing a future in which our knowledge and our ability to gain knowledge will have have become so great that we will no longer be able to definitively identify the species of a plant in the field or even under a laboratory microscope.

Anyone who has information that contradicts or supplements the above is welcome to contact me at: mmlcharters[at]calflora.net.

Photo identifications L-R: Emmenanthe penduliflora (Whispering bells), Equisetum telmateia (Giant horsetail), Crossosoma californicum (Catalina crossosoma)