SCAPHOPODA 1:5 1 



imperfectly known to justify'its reference to the Scaphopods, or even to the 

 MolluBca. 



r'amily 1. Dentaliidae. Gray, 



Scaphopoda ha rim/ ,< n,nic foot with an encir<-l/'n<i Outfit upanded laterally and 

 int'.-n-npted dorsallij. Shell tubular, curved, /vr////,//-/// tnf,, //,/,/ //,/ ,,/,/'/, not contracted 

 anteriorly, sculptured or smooth. Ordovirian t" Ueeent. 



Dentalium, Linii. (Figs. 789, 790). Character- those of tin- family. Heginiimg 

 with a few species in the Ordovician, tin- number inen-a.-e.- .-lowly until tin- ( jetaceou-. 

 A great acceleration then ensues, which continues to tin- piv.-ent. 

 About 275 fossil and 150 recent species known. Various authors have # 

 attempted to .subdivide the genus upon characters of the posterior .-lit 

 of the shell, but this has proved to vary widely even among individuals. 

 The following sub-genera based upon the system of sculpture and ,-hape 

 of the tube appear more >table : 



I filial in in. s. str. (Fig. 789). Shell with strong longitudinal ribs, apical 

 notch short or wanting. Eocene to Recent. 



.1, /f alts, Adams (Entails, Gray 11011 Sowb. ; 

 Entaliopsis, Newton and Harris), (Fig. 

 790, A}. Shell with longitudinal riblets or 

 striae at least in the young ; apex with a 

 short ventral slit and a sheath. Cretaceous 

 to Recent. 



Heterosehisma, Simr. With longitudinal 

 riblets and a dorsal slit. Recent. 



Fissidentalium, Fischer. Large and solid, 

 with many longitudinal ribs or striae ; a long 

 ventral slit usually present. Eocene to 

 Recent. Schizodentalium, Sowb., in which 

 the slit is interrupted into a series of holes, 

 is probably a modification of this group. 



tJi-iiptiiciin', Pils. and Sharp. Surface with 

 close, tine longitudinal striae near apex only, 

 or throughout. Tertiary and Recent. 



l.iifrl,!,-,!!, ilium, Cossm. Arcuate, smooth, 

 with growth-lines only, circular in section, 

 apex simple or notched. Silurian ? to Recent. 



Ithabdiis, Pils. and Sharp. Smooth, 

 glossy, nearly straight, sub-circular in section, 

 apex entire. Recent. 



ti/if.xijt/in. Pils. and Sharp. Small and very slender, smooth, the apex generally with an 

 inserted tube. Oligocene to Recent. 



Compressidena, Pils. and Sharp. Small, much tapering, vertically compressed, smooth. 

 Eocene to Recent. 



Lobantale, Cossrn. Shell compressed, with two internal longitudinal ribs. Eocene. 



Fustiaria, Stol. (Figs. 790, B, C). Shell with a very long and linear ventral cleft posteriorly. 

 Cretaceous to Recent. 



Pro. T'.' 



A, D. (A Htiii;*) Kni,., :, Nyst. ( 



oceiit- ; Wrinhcini. near Alxt-v. 

 D.(Fustiaria)lucida. Drsli. Eocene; 

 Guise la Mothe. Vi- <-', 

 portion of saiins 

 slit. 



\^- 



/,', 



Pip, 

 Denial 



"ii'inlmr, Lain. 

 Pliocene ; Asti, 

 Italv. 



Sars, J/., Oni Siphonodentaliiiin vitmim. en ny Slaegt af Deutalidernes Familie. rnivei>itots- 



Program, Christiana, 1861. 



Stoliczka, J>\, Palaeontologia Indica. Cretaceous Fauna of Southern India, vol. II., 1867-68. 

 Gardner, J. &, On the Cretaceous Dentaliidae (Quar. Jouru. Geol. Soc. London, vol. \.\.\IV. j.p. 



56-65), 1878. 

 Kovalevsky, A., ^tude sur rembryogenie, etc., du Dentale (Ann. Mas. iIi-4. Nat., Marseille, Zoologie 



Mem. No. I.), 1882-83. 

 Plate, L,, Ueber den Ban utid die \fr\vandtschafts-Bezieliungen der Solenocouchen (Zool. Jaln-1)., 



Abtheil. fiir Auat. und Ontog., vol. V. pp. 301-386), 1892. [Bibliography, pp. 384-386.] 

 Simroth, H., Mollusca in Broun's Classen uud Ordnuugen des Thierreichs, vol. III. pp. 356-467. 



1893-95. 



