242 SPURIOUS SCAPHOPODA I SERPULID^E. 



organisms are to be found in the opercula, gills, etc., rather than in 

 the tubes, which give characters of but little value to the modern 

 helminthologist. 



In early Tertiary and Cretaceous deposits there are several species 

 with solid, thick, heavily ribbed shells, such as Serpula heptagona 

 Sowb., ' D." rudis Gabb, etc. Their exact generic relations are not 

 known to me, but they are obviously members of the family Serpul- 

 idce, (see pi. 37, fig. 20, " D." abbreviation Dh.). 



The species are arranged alphabetically without regard to geologi- 

 cal horizon, and no attempt at synonymy, even when obvious, has 

 been made. 



Dentalium abbreviation Deshayes, 1825. Mem. Soc. Hist. Nat. 

 Paris, Vol. ii, p. 352, pi. xviii, figs. 21-22 ; see also Descr. Anim. s. 

 Vert. Bassin Paris, Vol. ii, 1864, p. 199, pi. 3, figs. 5-7 ; Eocene of 

 the Paris Basin(=" Serpula" heptagona Sow.). 



Dentalium arietinum Mu'ller, Zool. Danicse Prodromus, p. 236, 

 1776. 



Dentalium bulbosum Bronn, 1831. Ital. Tert. Gebild., p. 85 

 ("=D. entalis Brocchi in part "). See also EICHWALD, Lethsea 

 Rossica, iii, p. 136. STEFANI & PANTANELLI, Bull. Soc. Mai. Ital., 

 iv, p. 67. *' Unbekannte Versteinerungen " HOERNES, Foss. Moll. 

 Tert. Beckens Wien, in Abhandlungen der Kaiserlich-koniglichen 

 Geologischen Reichsanstalt, 1856, p. 664, pi. 50, f. 41. Pliocene, 

 Italy, Russia, etc. 



Dentalites cingulatus Schlotheim, Die Petrefactenkunde, p. 94. 



Dentalium carinatum O. G.Costa, Faun. Reg. Nap., Tubibranchi, 

 pp. 24, 52 (1851). 



Dentalium coarctatum Brocchi, 1814. Conch. Foss. Subapp., ii, 

 p. 264, pi. i, fig. 4. A Calabrian Pliocene Ditrupa f 



Dentalium corneum Linn., Syst. Nat. (12), p. 1263 (=Ditrupa 

 arietina). 



Dentalium cylindraceum Costa, 1850. Faun. Reg. Napoli, Dent., 

 p. 39, pi. 3, fig. 10=Ditrupa. Italian Pliocene? near Caramanico. 



Dentalium cylindricum Sowerby, 1814. Mineral Conch ology, 

 Vol. i, p. 179, pi. 79, fig. 2. Ems worth, England. According to 

 Gardner, this Ditrupa is a synonym of Dentalium planum Sowerby, 

 described on the same page. 



Dentalium deshayesianum Galeotti, 1837. Me*m. Couron. Acad. 

 Roy. Bruxelles, Vol. xii, p. 62, pi. 4, f. 7. Plateau D'Assche of 

 Brabant. 



