by Gary Rosenberg
Shell collectors are often frustrated by the inability to establish the correct name for a species. For the purist there is only one recourse -- diving into libraries and reaching one's own decisions. The first necessity is access to primary literature -- the original literature where the species were first named. Gaining access to primary literature can be difficult; this column gives some pointers on how to get a foothold.
There are only a few dozen institutions in the world, and fewer individuals, with natural history libraries comprehensive enough to answer most questions about mollusks. Because the catalogues of many major libraries are computerized, however, it is often possible to track down copies of desired works from scattered sources. Most research libraries will provide photocopies for a fee and, by this means, the conchologist can build up a substantial collection of original descriptions. If a computer search fails, another valuable resource is the National Union Catalogue, pre-1956 Imprints, which lists which research libraries in the United States hold what books. The NUC is gigantic, running to hundreds of volumes, and itself is held only by libraries of states, large cities and major universities.
In order to start requesting photocopies, you must at least have access to three important indices to the literature: Sherborn's Index Animalium, which covers 1758 to 1850; Ruhoff's Index to the species of Mollusca introduced from 1850 to 1870; and the Zoological Record: Mollusca, which covers 1864 to the present. These works generally tell only the page on which the description begins, so a request for photocopies must stress that the entire description is needed, along with any illustrations. Getting the entire article is preferable, if it isn't too long, since important information can appear in the introduction, or in entries for related species. Also make sure to get copies of the title pages of each book or journal; they will come in handy for tracking sources.
The first volume of Sherborn's Index Animalium attempts to list all species and genus names of animals published between 1758 and 1800, with their original citation. The next nine volumes cover species and genera from 1801 to 1850. Sherborn is about 95% complete for names of mollusks introduced between 1758 and 1850, and what he missed tends to be very obscure, so in practice, 99% of the time, one will find that Sherborn provides the exact page number in the book or journal where the species was named. Sherborn lists specific names in alphabetic order, with adjectives alphabetized in masculine form. This can be confusing at first, because, for example, "lata" (broad) will be alphabetized as "latus" and so come after "lateralis." Sherborn's system has advantages though, because all the forms of a name are in one block. For example, look up Cerithiopsis lata in the index of Abbott's American Seashells (1974); it is under "latum," three column inches away from "lata" and can easily be missed.
After 1850, matters are more difficult. Ruhoff lists species names for mollusks introduced from 1850 and 1870, but her work missed 30 to 40% of the names in this period and is weak for fossil mollusks. Ruhoff uses straight alphabetical order instead of taking into account gender of endings. From 1864 to the present day, the Zoological Record documents the place of publication of names, but to find a name requires knowing the year that it was published. Without the year, one must scan more than 130 volumes one by one, which is impractical. The last couple of decades of the Zoological Record are available online and can be searched for a fee. The Zoological Record is about 80% complete for species names of mollusks in the period it covers.
What if a name is not found in one of three works? One possibility is that the name was listed under a genus other than the one expected. These works list names under the original genus, which is not always easy to infer. For example, Röding (1798) named his species of Conus in the genus Cucullus and his Oliva in Porphyria. Scanning the list looking for names by the desired author might help. Zoological Record has an advantage here, because it groups names by family or superfamily, so it is easier to recognize likely candidates. Sherborn is most difficult in this regard, since names from other phyla are mixed in, so there will be lots of unfamiliar genera. (Sherborn also has additions and corrections in the last volume, which are often overlooked.)
Another possibility is that the name is one that these indices missed. The Royal Society Catalogue of Scientific Papers, 1800-1900, in 16 volumes, can then be helpful. It provides a list of articles by author, in chronological order. Often the title of the article flags it as the likely place where a name appeared.
What if one doesn't know the date of publication, or even the author? A Listing of Living Mollusca by Goto & Poppe (1996) is the best source, listing about 40-50% of valid, living mollusk species, with greatest strength in marine mollusks. However, it does not list names thought to be synonyms, and so lists fewer than 25% of available names for mollusks. Goto & Poppe is essentially an index to most of the books and major monographs on mollusks published in the last 30 years, and so points to secondary sources that might lead one to primary sources.
Many other books and monographs might be useful for tracking down original descriptions in particular families or faunas. For example, the bibliography in Keen (1971, Sea Shells of Tropical West America) lists most of the papers where the species she treats were described, although without stating on what page particular species appeared. Vokes (1971, Bulletins of American Paleontology 61) gives the original citation for species named in the genus Murex. My own database on Internet provides citations for more than 6000 names of Western Atlantic gastropods (URL http://erato.acnatsci.org/). These pre-existing lists can save months or years of effort.
If there is no list for a particular taxon, or the existing list is out of date, Sherborn, Ruhoff and the Zoological Record can be used to create a list. This is much more productive in the long run than tracking down names piecemeal as they are encountered in the secondary literature. Sherborn and Ruhoff both have indices by genera, so one can get a list of all the names in a particular genus. For example, a quick count in the index shows that Sherborn list 149 names of Haliotis. Having compiled a preliminary list of names and citations in this fashion, one can request photocopies much more efficiently. It can be quite frustrating to get a photocopy of an original description and then discover two months later that there was congeneric species named in the same paper.
Beware in Sherborn, because if there are two genera with the same name, they are not distinguished in the index (although they will have separate entries in the text). For example most names of Chlamys in Sherborn are beetles of the genus Chlamys Knoch, 1801 rather than scallops of the genus Chlamys Röding, 1798. (Such non-molluscan names can safely be ignored. ICZN rules state that homonymy between the same specific name in homonymous genera is to be disregarded, so the beetle Chlamys reticulata Klug, 1824 does not preoccupy the scallop Chlamys reticulata (Reeve, 1853). The beetle genus was renamed Arthrochlamys.)
Ordering photocopies goes only so far. There are inevitably citations that cannot be tracked down and works that cannot be found. Seeing colored illustrations can be essential for understanding what an author meant. At this point, it's time to visit one of the major natural history libraries. With appropriate preparation, more can be accomplished in a week on site than in a year of correspondence with librarians, however helpful they may be. Of course, once the literature is in hand, one must know how to use it to determine the correct name for species. That will be the subject of September's column.
- Ruhoff, F. A. 1980. Index to the species of Mollusca introduced from 1850 to 1870. Smithsonian Contributions to Zoology no. 294, 640 pp.
- Sherborn, C. D. 1902. Index Animalium, 1758-1800. Cambridge: Cambridge University Press. 1195 pp.
- Sherborn, C. D. 1922-1932. Index Animalium, 1801-1850. 9 vols. London: British Museum (Natural History). 6357 + 1098 pp.
Department of Mollusks, Academy of Natural Sciences, 1900 Benjamin Franklin Parkway, Philadelphia, PA 19103-1195