296 



DENTALIUM. 



Dentalium subfissura, Tate (sp.). 



1887. Entalis subfissura, Tate, Trans. Roy. Soc. South Aust. vol. ix. p. 191, 



pi. XX. figs. ia-b. 

 1893. Entalis subfissura, Tate and Dennant, id. vol. xvii. pt. 1, p. 223. 

 1895. Entalis subfissura, Tate and Dennant, id. vol. xix. pt. 1, p. 112. 



The shell of this species is smooth and polished, but possesses 

 almost obsolete annular strife with more prominent lines of growth. 

 The posterior fissure is a triangular notch, the sides of which 

 are slightly reflected outwardly. It may be easily differentiated 

 from D. fissura, Lamarck, of the Paris Basin, with which the 

 author compares it, in that the fissure in the European species 

 is much longer. 



Dimensions. — Length 45 mm. ; width of anterior aperture 4 mm. 



Form, mid Loc. — Eocene : Victoria. 



48052. Two examples of the adult ; from Hobson's Bay. 



Purchased. 



G. 9389. Two specimens, one of which is sharply curved 



near the posterior end ; from Muddy Creek. Purchased. 



Dentalium acriculum, Tate (sp.). 



1887. Entalis acriculum, Tate, Trans. Eoy. Soc. South Aust. vol. ix. p. 192, 

 pi. XX. fig. 11. 



This species very closely approaches D. fissura, Lamarck, of the 

 European Eocene, differing from it principally in not having such 

 a long fissure, in the latter being slightly twisted and enlarged 

 anteriorly, and in the shell being annularly constricted at irregular 1 

 intervals. It is narrower and not so much curved as B. subfissura, 

 whilst its fissure is not triangular, but linear; otherwise the two] 

 species are closely allied to each other. 



Dimensions. — Length 33 mm. ; width of anterior aperture] 

 2*5 mm. 



Fortn. and Loc. — Eocene : Muddy Creek, Yictoria. 



G. 9388. Series illustrating stages of growth. Purchased. 



