TURRITELLID^, 225 



not reflected in front, onter lip somewhat thickened within. 

 T. lanceolata, Reeve (Ixvii, 61). 



MATHILDA, Semper, 1865. Shell turriculated, apex revolute, 

 abruptl}^ turned from left to right ; whorls in the typical species 

 transversely^ cingulated and reticulated, longitudinally striated ; 

 aperture entire, subrotund,base sometimes subetfuse ; lip acute; 

 columella smooth. T. cochlseformis , Brugn. (Ixvii, 62). Med- 

 iterranean; and several fossil species. Jurassic — ; Europe, 

 United States. 



GLAUCONIA, Griebel, 1852. Shell turriculated, subulate ; aper- 

 ture small, roiinded, peristome continuous, forming a posterior 

 angle. Fossil. T. Maraschini, Defrance (Ixvii, 63). 



CASSIOPE, Coquand, 1866. (Omphalia, Zekeli, 1852 [not Om- 

 phalius,Phil.]. Proto, authors, not Defrance.) Shell thicker, and 

 with more rapidly increasing whorls than in Turritella, often 

 pupiform ; aperture rounded, continuous ; outer lip notched or 

 sinuated by an impressed furrow, which winds round the last 

 whorl ; columella usually distinctly umbilicated. There are 30 

 cretaceous species. Europe, India and America. C. Menevieri^' 

 Coquand. 



ARCOTIA, Stoliczka, 1868. Shell turreted, elongated, somewhat 

 thickened ; whorls spirally striate ; incremental striae straight, 

 not sinuated ; columella excavated ; aperture angulately rounded, 

 subetfuse anteriorly. T. Indica, Stol. (Ixvii, 64 , Jurassic 

 and Cretaceous ; India. 



Protoma, Baird, ISTO. 



Distr. — P. Kvockeri, Baird. Whydah, W. Africa. 



Shell turreted, aperture oval, narrowly excised at the base. 

 Operculum circular, corneous, multispiral. 



The operculum shows this to belong to the Turritellidse, 

 although the aperture of the shell is more like that of Terebra. 



LiTHOTROCHus, Conrad. 

 Approaching Mesalia, but without the produced basis of the 

 last whorl of that genus. There is a thickened sutural band, 

 with very numerous growth-striae. Has much the appearance of 

 an elongated Trochus. Liassic. L. Humboldtii, Buch. (Ixvii, 

 65, 66). South America. 



Cochlearta, Miinster. 



Syn. — Chilocyclus, Braun. 



Distr. — 2 fossil sp. Triassic ; Austria. G. carinata, Bronn 

 (Ixvii, 61). 



Shell turriculated, thick; aperture rounded, peristome con- 

 tinuous, widely and flatly reflected all around. 



Zittel considers this a group in the family Scalaridse. 



