PARTULA. 159 



Coarsely wrinkled, the upper portion densely granulose and 

 coarsely plicate. The retractor muscle is terminal. The vas 

 deferens opens below a papilla situated at about the lower 

 third of the granulose portion ; it is therefore not terminal on 

 the penis. It is superficially bound to the penis, to the 

 vagina and the basal part of the spermatheca, then free as 

 far as the upper end of the oviduct, where it is again adnate 

 for a short distance. The ovisperm duct is strongly knotted, 

 as usual. The 'basal part of the spermatheca-duct is much 

 swollen in P. rosea and P. fusca, the distal end tapering; 

 but in P. bilineata (pi. 43, fig. 3, after Binney) umbilicata, 

 virginea, otaheitana and hyalina the spermetheca is oblong, 

 obtuse distally, and seated upon a slender duct. In all the 

 species which have been examined the duct is short. 



Reproduction seems to 'be ovo-viviparous. The upper part 

 of the oviduct contains oblong egg-capsules having a cal- 

 careous shell, which lower down in the oviduct becomes dis- 

 solved or is consumed by the embryo. From one to five eggs 

 or young are found in one individual. 



Free muscles: In P. rosea (pi. 43, fig. 4). The pharyngeal 

 retractor is free to its proximal insertion. At about the 

 middle of its length the left ocular and tentacular retractor 

 band joins it, and a little farther out the anterior pedal re- 

 tractors branch off. The broad posterior pedal retractor 

 (tail retractor or columellar muscle) remains united far 

 forward with the right ocular and tentacular retractor, which 

 gives off a group of small anterior pedal retractor muscles. 

 The right ocular band passes between the male and female 

 branches of the genitalia. 



This muscle system differs from that of Achatinella dolei 

 chiefly by the union of the right ocular with the tail retractor. 

 In Achatinella both ocular bands are free. 



Relationships of Partulidc?. 



This family is one of the most sharply defined in the 

 Orthurethra. By its short kidney, about equal to the 

 pericardium, it differs conspicuously from the Enidce, 



