STROBILOPS. 13 



StroUlops PiLSBRT, Proc. A, N. S. Phila. for 1892, p. 403 

 (Feb. 7, 1893), a substitute for Strohila Morse; Nautilus, VI, 

 1892, p. 56; XXII, 1908, p. 78. — Hanna, Nautilus, XXV, 

 1922, p. 91 (anatomy). — ^Wenz, Neues Jahrbucli fiir Miner- 

 alogie, Geologic unci Palaontolo^e, 1915, II, pp. 63-88 (synop- 

 sis of Tertiary species) ; Nachrichtsblatt d. Deutschen Malako- 

 zoologischen Gesellschaft, 1916, pp. 178-192 (synopsis of 

 Eecent species) . 



The shell is small, perforate or umbilicate, trochiform to 

 subdiscoidal, with rounded, angular, or carinate periphery, of 

 4% to 6 closely-coiled whorls. Cavity of the last whorl is 

 obstructed by two or three long parietal lamellse, the upper 

 one emerging to the edge of the parietal callus, the lower one 

 weaker, emerging or immersed, the intermediate one when 

 present, smallest and remote from the aperture; a series of 

 two or more short folds on the basal wall of the cavity deep 

 within the last whorl. These lamellas and folds appear very 

 early in life, grow at the forward end and are absorbed be- 

 hind. Peristome expanded, usually thickened, the insertions 

 of the lip remote, connected by a parietal callus. 



The sole is short and broad, in movement showing two or 

 three advancing muscular waves at one time ; no pedal grooves. 

 The integument has a network of impressed lines. Eyes arei 

 well-pigmented, on eye stalks a little swollen distally. Ten- 

 tacles short but moderately well-developed (pi. 4, figs. 9, 11, 

 S. lahyrinthica) . 



Anatomy according to Hanna. — The kidney is long and nar- 

 row, passing anteriorly into the long urethra (ur.) which lies 

 close to the intestine (g) and opens near the breathing pore 

 (pi. 4, fig. 8). Genitalia (pi. 4, fig. 7, S. lahyrinthica) : Ovo- 

 testis (ot) composed of follicles in two groups, imbedded in 

 the liver. The lower portion of the spermoviduct {h. d.) is 

 thick and strongly convoluted. Albumen gland with finely 

 granulose surface. The prostate forms a ''series of lamellar 

 pouches." Vas deferens is long, passing below into a rather 

 thick and very long epiphallus {ep.). Penis {p) is rather 

 stout in the lower half, abruptly becoming thin in the upper 

 (or possibly this thin portion is part of the epiphallus; a ques- 

 tion to be settled by opening the organ) . It bears a very long 



