COCKERELt : THE HRLICOID GROUP CALLINA LOWE. 3II 



(but abraded); short coarse plicae on the last two whorls below the 

 suture ; base flattened, little convex ; lip very thick with a rather 

 short basal callus within, apically descending gradu- 

 ally, not truncate ; no well defined parietal callus ; 

 aperture rather narrow, semi-lunar, except for the 

 y interruption of the outline due to the basal callus ; 

 umbilicus entirely closed, covered by a large spread- 

 ing callus, broader than that of O. obserata. 



It seems desirable to add a note on the systematic position of the 

 genus Ochthephila, which has remained obscure in the absence of any 

 knowledge of the genitalia. I obtained a very good series of the soft 

 parts of a number of species, which I handed to Dr. Pilsbry for 

 detailed description. On dissecting a specimen of O. pulvinata 

 (Lowe), from the north side of Porto Santo, I find a highly developed 

 epiphallus, but no dart-sac or filiform glands. The characters are 

 those of Pilsbry's group Epiphallogona, which in his phylogenetic 

 diagram he makes ancestral to the Belogona. Thus it would appear 

 that Ochthephila represents the survival of a type of Helicidse which 

 is now mainly developed in the Oriental and Australian regions. It 

 is to be said, however, that I find in O. pulvitiata a slender cylindrical 

 organ about 1120 microns long and no broad, which appears to 

 correspond exactly in position and in shape (though very much 

 smaller) with the ca;cum or supposed degenerate dart-sac of Theba 

 cantiana. If this structure is really a degenerate dart-sac, then 

 Ochthephila may be a member of the Belogona which, through 

 degeneration, simulates the Ephiphallogona. The spermatheca in 

 O. pulvinata is large, claviform, not at all boot-shaped. The penis 

 (within the sheath) is very obtuse and rounded, at least in the speci- 

 men examined. 



When in Porto Santo, I superficially examined the anatomy of 

 O. consors (Lowe), and also found no dart-sac. In consors the stout 

 flagellum terminates in a nipple-like papilla. 



