186 HBLICID^E. 



narrow, nearly or quite the length of the pericardium. Ureter 

 reflexed, the secondary ureter a closed tube. 



" Muscles : Betractor of the penis inserted on the diaphragm 

 as usual. The pharyngeal retractor is united to the right ocular 

 and pedal band far forward ; the left ocular muscle passes to the 

 right of the genitalia, not between the male and female branches. 



"Jaw well arched, thin, with its lower margin crenulated by 

 10-14 flat ribs, which seem separated by narrow intervals in the^ 

 median part, but are contiguous or overlapping towards the ends. 

 It is similar to that of some species of Papuina, intermediate 

 between the plaited and the ribbed types. 



" Radula of the usual form in Helicida?. The transverse rows 

 of teeth bent at a wide angle in the middle. Rhachidian and 

 admedian teeth with single, long, broadly rounded cusps. These 

 pass by a gradual transition to the lateral type, in which the tooth 

 is inclined and bears a three-lobed cusp. 



" The shell does not have the brilliant coloring of many 

 Amphidromus, and is minutely pimctulate, at least on the spire. 

 The area of distribution is separated from that of true Amphi- 

 dromus. I have elsewhere shown that Beddomea agrees with 

 Amphidromus in the long, band-like kidney, the pattern of lung- 

 venation, the arrangement of the muscles (except the eyes and 

 retractors), the reproductive system, and the jaw. It differs from 

 Amphidromus in having the eye retractor muscles to the right of> 

 instead of between the branches of the genitalia, in having the 

 cusps of the teeth of the median fold of the radula broadly 

 rounded and simple instead of deeply cloven into three cusps, as 

 all the side-teeth are in the restricted group of Amphidromus ; and 

 finally in having the radula longer than in Amphidromus. 



" In view of the general agreement, it scarcely seems well- 

 advised to accord Beddomea higher rank than that of a subgenus 

 of Amphidromus. None of the three structural differences 

 mentioned is of much importance, though I do not doubt that 

 they will prove constant in Beddomea. "When some of the species 

 of Amphidromus which are conchologically nearest; Beddomea 

 (such as A. sylheticus) come to be examined, transitions may not 

 unlikely be "found in the dentition. In the long flagellum, 

 Beddomea is more like the larger, amphidrome species of Amphi- 

 dromus than the smaller, invariably sinistral species, which, so far 

 as known, have this organ much shorter." (Pilsbry.) 



Key to the Species. 



i. Solid and opaque, variegated with brown bands or 

 stripes. 



a. Shell elongate-conoid trifasciatus 



b. Shell pyramidal bontice. 



ii. Rather thin, very pale or white, without dark 



markings. 



