Phylum Name

Rev:  01/01/2020

The English word "Nema" Revised


[Reprinted from Systematic Zoology in Nematology Newsletter 4(45):1619 (Dec. 1999)].

Many years have passed since Cobb (1919) published his article on the classification of the phylum "Nemates." He had previously (1917) used the word "nemas," though, in the same article, the word "nematodes." In 1931 he published an excellent diagnosis of the phylum in his presidential address before the American Society of Parasitologists and in 1932 used a title here included in the title of this article — namely "The English word ‘nema,’ explaining the derivation of the word ‘nema’ and proposing various derivatives from it."

As Cobb pointed out, the term "nematode" is a contraction or vulgarity for nematoid and a weaker term since it means "thread like," while nema means "thread." In the same article he published various derivatives of the word nema, i.e., "nematicide," "nematosis," "denematize," and pointed out the value of their usage.

Zoologically speaking, the vernacular word "nematode" is a corruption of the ordinal name NEMATOIDEA of Rudolphi (1808, pp. 197, 198). It was already in use — in its German plural equivalent "Nematoden" — at least by the time of Wiegmann (1835, p. 336), who, however, continued "Nematoidea" for the taxon itself. Beginning with Burmeister (1837, n.v.), the stem nematod was used by some workers for a formal zoological group — in Burmeister’s case for a Familie NEMATODES. Subsequently, both R. Leuckart (1848, p.77) and von Siebold (1848, p. 112) employed an Ordo NEMATODES, which Diesing (1861, p. 598) modified to Ordo NEMATODA. Vogt (1851, p. 174) first proposed the name NEMATELMIA for a Klasse to include the Ordnungen NEMATOIDEA, GORDIACEI, and ACANTHOCEPHALA. This name was modified to NEMATHELMINTHES by Gegenbaur (1859, p. 137) and NEMATELMINTHES by Carus (1863, p. 456). Later, both NEMATOIDEA and NEMATHELMINTHES were promoted to phylar rank. Since the grouping of nemas, horsehair worms, and thorny headed worms (acanthocephalans) has never been a sound zoologic concept, the names Nematelmia, Nematelminthes, and Nemathelminthes should be dropped, as they have been by most thinking zoologists in recent years.

As originally proposed by Rudolphi (1803, 1809), the order Nematoidea contained some species that were originally described as gordiids (horsehair worms) and that later workers placed in synonomy with gordiids. Von Siebold (1843, p. 302) created and Ordnung GORDIACEI, coordinate with the Ordnung NEMATOIDEA, but incorrectly associated the nemic genus Mermis with the horsehair worms of the genus Gordius. This continued to be true for much of the remaining half of the 19th century. Huxley (1864, p. 47) promoted the horsehair worms provisionally to a Class GORDICEA, coordinate with a Class NEMATOIDEA in a category SCOLECIDA (which he treated as a class, or alternatively as some unspecified higher category containing the classes Nematoidea, Cordiacea, etc.) However, it appears probable, on the basis of later publications by him (Huxley, 1877, p. 641, in which he reverted to a group NEMATOIDEA—of unspecified rank but containing as "Groups" Polymyaria, Meromyaria, and Holomyaria, in the last of which he included Gordius), that in 1864 he had no better concept of the Gordiacea than had von Siebold in 1843. Such was equally the case with Lankester (1877, p. 449), who promoted the NEMATOIDEA to the level of phylum, but included therein, as a "subdivision," the GORDIIDAE. The first clear distinction between the nemas and gordiids wasVol. 45 (4) 17 realized by Vejdovsky at which time he named a group to contain the horsehair worms the order NEMATOMORPHA (1886, Rad [=Order], p. 634).

There is no question that Cobb first proposed the Phylum Nemates in 1919 and gave a diagnosis in 1932. The fact that Potts (1932) and the writer in 1950 did not recognize Nemata Cobb, 1919, but rather synonymized it with the Nematoda (as a phylum) is lamentable. We can only say that the writer was young, foolish, and ignorant and did not realize the far-reaching importance and soundness of Cobb’s work. The values of the derivative words and, in particular, the saving in time of secretaries and clerical workers and in costs of publication resulting from the shortening of "nematoid" or "nematode" to "nema" were not impressed on him at the time. If he had realized that the group was a sound phylum when the first part of "An Introduction to Nematology" was written starting in 1937 (see Chitwood, 1937, 1940), and particularly if he had paid proper heed to Cobb’s work when preparing the revised edition, which appeared in 1950 (see Chitwood 1950), this article might not be necessary. He can only plead ignorance and request all good people to drop that corrupt word nematode, remember of course, that they are not toads (even though a farmer once asked what kind of toads they were), and thus not use it in polite company!

The following is a reproduction of Dr. Cobb’s (1932) article, which is out of print and written much better than the author could write it:

"For thousands of years the word ‘nema’ has been a household word, the Greek word for ‘yarn’ or ‘thread,’ and was introduced, unaltered, into Latin. As a suffix it enters into a large number of English technical words (less often, as a prefix) and as such has a place in all large dictionaries.

"The word ‘nema,’ meaning a nematoid or nematode, has been used for some years in the publications of a number of reputable authors, and its use is increasing, largely, no doubt, because it lends itself very readily to formation of euphonious derivative having precise and obvious meaning — words widely useful in the literature of parasitology and medicine. ‘Nematologist’ and ‘Nematology’ are established words in the business of the U.S. Department of Agriculture and occur in acts of Congress.

"This use in English of the word ‘nema’ by itself is simply a slight modification of the usage of generations of scholarly naturalists who have coined such words as Pontonema, ‘sea nema,’ coined by Leidy, Ichthyonema, ‘fish nema,’ coined by Diesing, and Allantonema, ‘sausageshaped nema,’ coined by Leuckart."

This is such well established usage that there are well toward a hundred genera of nemas whose names end in the syllables ‘nema.’ In following and extending this long established custom, one is simply accepting a metaphorical use of the word ‘nema,’ so that it is in reality only a slight and obvious step to admit it in this form as a common English word. Not only does it lend itself readily to the formation of useful derivatives but it is preferable to ‘nematoid’ or ‘nematode’ in that it is shorter and makes use of a more forceful form of speech, the metaphor. The word ‘nema’ has more force than ‘nematoid’ in accordance with the general law that the metaphor is more forceful than the simile. An obstinate or stupid person is said to be ‘asinine’ (simile) but, far more forcibly, is said to be an ‘ass’ (metaphor). In a similar way it is more forceful to call an organism a ‘thread’ (nema) than to call it ‘threadlike’ (nematoid), and here, as usual, the metaphor is the shorter form. The plural ‘nemas’ is preferred to ‘nemates,’ just as ‘lemmas’ is preferred to ‘lemmates’ and ‘edemas’ to ‘edemates.’ "


1. Burmeister, H. 1837. Handbuch der Naturgeschichte. Zum Gebrauch bei vorlesungen entworfen.3 2 S Abt.: Zoologie., Pp. 369858, Berlin.

2. Carus, J. V. 1863. Raderthiere, Wumer, Echinodermen, Coelenterated und Protozoen, In Carus, J.V., and Gerstacker, A., Handb. Zool. 2: 422600. Leipzig.

3. Chitwood, B. G. 1937 General structure of nematodes. Chap. II in Chitwood, B.G., and Chitwood, M. B., An Introduction to Nematology, Sec. 1, Part 1, pp. 727. Baltimore.

4. _____1940. Nemic relationships. Chap. XIII, In: Chitwood et al., Ibid., Sec. 1, Part III, pp. 190204. Babylon, N.Y.

5. _____1950. Idem. Chap. XIII, in: Ibid., Sec. 1, anatomy, pp. 191205, Revised Ed. Baltimore.

6. Cobb, N. A. 1917. Notes on nemas. Contrib. Sci. Nematol., No. V, pp.213216.

7. _____1919. The orders and classes of nemas. Ibid., No. VIII, pp. 213216

8. _____1931. Some recent aspects of nematology, Science, 73(1880):2229.

9. _____1932. The English word "nema." Jour. Amer.Med.Assoc., 98(1):75

10. Diesing, K. M. 1861. Revision der Nematoden. Sitzungsber. K. Akad. Wissensch. Wien, MathNaturw. CI. (1860), 42 (28):595736, 1pl., figs, 112.

11. Dropkin, V. H. 1955. The relations between Nematodes and plants. Exper. Parasitol., 4(3):282322.

12. Gegenbaur, C. 1859. Grundzuge der verglei Chenden Anatomie. XIV + 606pp. Leipzig.

13. Huxley, T. H. 1864. Lectures on the elements of comparative anatomy. Xi + 303 pp., 111 figs. London

14. _____1877, A manual of the anatomy of the Invertebrated animals. Viii + 698 pp., 158 figs. London.

15. Lankester, E. R. 1877. Notes on the embryology and classification of the animal kingdom; comprising a revision of speculations relative to the origin and significance of the germlayers. Quart. Jour. Micro. Sci. n.s., 17:339454, 17 figs., pl 25 (figs. 120).

16. Potts, F. A. 1932. The phylum Nematoda. Chap. VII in Borradaile, L.A., and Potts, F.A., et al., The invertebrata. A manual for the use of students, pp. 214227, figs. 166 171. Cambridge and New York.

17. Rudolphi, C. A. 18081809. Entozoorum sive Vermium Intesstinalium Historia Naturalis, Vol. 1+2, 527 pp. & 457pp. (Resp.) Amstelaedami.

18. Von Siebold, O. 1843. Bericht uber die Leistungen im Gebiete der Helminthologie wahrend Des jahres 1842. Arch. Naturgesch., Berlin, 9.I., 2:300355.

19. _______1848 Lehrbuch der vergleichenden Anatomie der wirbellosen Thiere. 1. Theil, Wirbellose Thiere, in v. Siebold and StanNius, Lehrbuch der vergleichenden Anatomie, Berlin.

20. Veidovsky, F. 1886. O strunovicich (Gordiidae) okoli Prazskeho, s pozoamkami o jich morfologii. Zpravy o zasedani k. ceskespolecnosti Nauk, Trida MathematVol. 45 (4) 19 ickoprirodovidecka I=Sitzungsber. K. Bohm. Gesellsch. Wissensch., MathNaturwiss Classe). J.1885:620640. (An expanded version was printed in German later in 1886: Zur Morphologie der Gordiden. Zeit wissen. Zool., 43(3):309433.)

21. Vogt, C. 1851. Zoologische Briefe, vol 1.

22. Wiegmann, A. F. A. 1835. Bericht uber die Fortschritte der Zoologie im Jahre 1834. Arch.Naturg., Berlin, 1.J., 1(3):301361.