244 NILS HJ. ODHNER 

‘b 
Fig. 18. Nepionic shells of Zornatellinidae. a—h, * 50; 7, X 25. a, Tornatellina bilamellata 
(typical form), palatal fold feeble; 4, the same, a smaller shell (2 whorls); c, the same, a narrow 
variety with less pronounced angularity of the last whorl; in a brood of 6 young ones this was 
somewhat narrower and less angled than the remaining shells; d, the same, a three-toothed 
variety, young shell with 2 palatal folds, columella with an inferior callus, no angularity of the 
whorls; e, 7. comica (note the long parietal fold); 4, 7. callosa, a single nepionic shell, with 2 
whorls, from the toothed ephebic stage; g, 7. Alicosa, a nepionic shell, with 21/2 whorls, from 
the toothless ephebic stage; 4, Mernandezia cylindrella, a nepionic shell with 21/2 whorls; 
2, F. bulimoides, a nepionic shell with 2 whorls. 
theca with a very long stalk; the bladder is situated upon the prostata gland. 
There are no other accessory formations attached to the female portion. 
The vas deferens follows the stalk of the spermatheca down to closely 
inside the genital orifice. Its course is entirely straight, till it debouches in the 
vestigial penis which is. represented by a mere papilla as in Yornateliina. 
