SUB-ORDER B 



PLATYPODA 



465 



Lithoylyphus, Ziegl. (Fig. 908). Globose or ovate, with short spire; ratln-r thi'-k 

 and solid. Aperture large, obliquely oval ; inner lip thickened. 

 Tertiary and Recent; Europe. Similar forms, Somatoyyrus, (lill, 

 and Flumincola, Stimpson, occur in North America. There ae 

 other related genera in South-Eastern Asia and South America. 



Pro. i08. 



Ufhoglypkus fu&cus, 

 Xic-l.-r. Upper Mio- 

 cene ; Mali no, West 

 Slavonia. 



Family 11. Rissoidae. Troschel. 



Shell small, thick, turbinate to turreted, usually ribbed or spirally 

 striated, rarely smooth. Aperture oval, angular posteriorly, often with 

 anterior canal. Operculum 



horny, pa ucispiral. Jura to ' B A 



Recent. 



Rissoina, d'Orb. (Fig. 

 909). Turreted, transversely 

 ribbed, rarely smooth ; outer 

 lip arcuate, generally 

 thickened ; aperture some- 



FIG. 910. 



FiG. 909. 



.!, Rimotaa amoeno, Zitt Tithon- 

 what notched or effuse at ^L^JiS' SS^sSuf: 



the base. Dogger to Recent ; brunn, near Vienna, 

 mainly Tertiary. 



Rissoa, Frem. (Fig. 910). Turreted, transversely ribbed or cancellated, aperture 

 entire below. Jura to Recent. 



A, Rissoa turbinnl". Lain. sp. 

 Oligocene ; Wcinlit-im, near 

 Alzey. If, /.'. (Aim it!") M<,,>- 

 tugui, Payr. Miocene ; Steina- 

 brunn, near Vienna. 



Family 12. Turritellidae. Gray. 



Shell turreted, with high acuminate spire. IVlwrls numerous, usually spirally ribbed 

 or striated. Aperture oval, round or quadrangular, sometimes with faint anterior canal. 

 Outer Up thin, peristome discontinuous. Operculum horny, 

 multispiral. Marine. Trias to Recent. 



Turritella, Lam. (Figs. 911, 912). Spire very high; 

 aperture oval or rounded quadrilateral ; outer lip thin, 

 excavated behind, and slightly produced in front. Trias 

 to Recent ; maximum in Tertiary. The older Mesozoic 



species are usually 

 small. 



Sub-genera : Me- 

 so/to, Gray (Fig. 912). 



Like the last, but 

 aperture with shallow 

 canal, and twisted 

 inner lip. Tertiary 

 to Recent. 



Protoma, Baird 

 (Proto, p.p. Defr.). 

 Aperture oval, an- 

 teriorly with canal- 

 like contraction, 

 which is surrounded 

 externally by a thick 

 swelling. Tertiary 

 and Recent. P. 

 cathedralis, Brgt. 



Glauconia, Giebel (Omphalia, Zekeli ; Cassiope, Coq.), (Fig. 913). Thick-shelled, 

 conical to turreted, narrowly umbilicate. Whorls spirally ribbed, rarely smooth. 

 VOL. I 2 H 



FIG. 911. 



A, Turritella turris, Bast. (T. 

 terebra, Ziet. non Linn.)- Mio- 

 cene Molasse ; Ermingen, near 

 Ulin. li, T. imbricataria, Lain. 

 Calcaire Drossier ; Grignon, near 

 Paris. 



FIG. 912. 



TwrriteOa (Mesalia) 

 multisulcuia, Lain. 

 Eocene; Calcaire 

 Grossier ; Grignon, 

 near Paris. 



FIG. 913. 



(rlauconia Kefersteini, 

 Goldf. Middle Cre- 

 taceous ; Dreistatten, 

 near Wiener-Neust. 



