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The shell is smooth except from strong striae of growth, and oc- 

 casional folds as in other species of this group, the casts are all per- 

 fectly smooth.- A specimen from Phillipsburg has identical 

 form and position of siphuncle, and is in collection of Museum of 

 Comp. Zoology. 



Falcilituites. 



This genus set apart by Remele, the type selected being Lituiles 

 Decheni equal to Discoceras subcostatum Ang. et Lindstrom.* This 

 species has a very close-coiled whorl in the nepionic stage, the um- 

 bilical perforation not being figured at all by Angelin and Lind- 

 strom, a fact of essential importance when comparing this type with 

 Estonioceras. The coiled volutions are three in number according 

 to their figures, but the centre may be erroneously drawn. 



The shell has a decidedly quadragonal whorl like that of some 

 species of Schroederoceras, and the abdomen is even slightly con- 

 cave along the median portion? The lines of growth are strongly 

 marked and have a different aspect from those of Estonioceras. 

 The hyponomic sinus is deeper and broader and apparently the 

 lateral lines rise towards the dorsum in crests, but these really join 

 across the dorsum, forming one huge broad, dorsal crest. In other 

 words, if figured correctly, the aperture on the free volution must 

 have had a very deep hyponomic sinus and huge projecting dorso- 

 lateral crests undivided by any dorsal sinus as in Estonioceras. The 

 closely coiled volutions may have had lines of growth with dorsal 

 sinuses, but if so these disappeared on the free part of the whorls. 

 These volutions may also have had a contact furrow, but it must 

 have been slight, since it entirely disappears on the early part of the 

 free volution in both of the European species mentioned below. 



The sutures have also ventral saddles with deep lateral lobes. 

 Dorsal sutures are not given. 



The siphuncle is much smaller than in Estonioceras and is nearer 

 the, centre, being but little above this point or centroventren. This 

 organ is ellipochoanoidal according to Angelin and Lindstrom 

 figures which are very clear and apparently exact. 



There are only two species as yet described, Falcilituites Decheni 



*I have not been able to obtain from any library in this vicinity Remele's principal 

 works, bnt there is no doubt that he selected Discoceras subcostafinn, as described by 

 Angelin and Lindstrom. His papers were published in the Festsch. 50 jahr. Jith'/. a. 



Forstakarf. Ebcrsualdc, and the Untcrsuch. u. d. vcrslcincrngsf. Diluvial., etc. 



