176 VALLONIIDAE. 



serted on epiphallus and appendix. The prostate gland is 

 small and posterior. The spermoviduct is strongly con- 

 voluted. Albumen gland multilobular. Uterus much dis- 

 tended by the contained embryos, its neck much shorter than 

 the vaginal part of the oviduct. Spermatheca is oblong, but 

 little larger than its duct, which is of medium length, with- 

 out diverticulum. 



Zoogeiietes differs from Acanthinula chiefly by the absence 

 of appendages on the epipliallus, the shorter spermathecal duct 

 and the viviparous reproduction. It is more like Vallonia in 

 the genitalia. 



SPERMODEA Westerl. 



Vol. 27, p. 186. Specimens possessing the penis have not 

 yet been dissected. Without it, the position of the genus can 

 not be closely estimated. 



PLANOGYRA Morse. 



Man. Conch, vol. 9, p. 45. Dr. H. Burrington Baker has 

 shown that this genus is related to Acanthinula. See page 

 197, pi. 26, figs. 1-3. 



Genus SPELAEODISCUS Brusina. 



Vol. 27, p. 180. This genus was associated with Pagodulina 

 on account of some slight similarities in the shells. The ana- 

 tomical work and figures of Soos (1917, p. 65, figs. 39-42), 

 partly reproduced here, p. 175, figs. 9 h, c, show a long ap- 

 pendix, contracted in the middle, as in various Valloniidae. 

 There is a thick "flagellum", and the penial retractor is 

 forked. The spermathecal duct is short, as in Vallonia and 

 Zoogenetes. The prostate gland, composed of very long 

 tubules, shows unusually strong development. 



Steenberg (1925, pp. 184, 202) suggests a subfamily 

 Spelaeodiscinae, which he includes with some doubt in the 

 Valloniidae. Watson (1920) judging by the figures of Soos, 

 considered the genus allied to Vallonia and Acanthinula. 

 This position appears to me to be logical. The resemblance 

 of Spelaeodiscus to StroMlops mentioned by H. B. Baker seems 



