247 



aperture, turned up on a plane with the spire, by which it may be 

 seen that the living animal protruding from it would crawl with the 

 apex downwards. 



Genus 10. PROSERPINA, Gray. 



Animal ; undescribed. 



Shell ; depressly orbicular, polished, shining ; aperture furnished 



071 either side ivith strong, winding, tooth-like plaits ; lip simple, 



never reflected. 



The few species that have been associated under this head differ from 

 the ordinary Helix type in being of a polished, shining substance, generally 

 bright-yellow or greenish, characterized by having the interior furnished 

 on either side with strongly-developed winding plaits. The shell is never 

 umbilicated, nor is the lip ever reflected. It does not appear that the 

 animal has been observed. 



One species, P. eolina, is from Mexico ; the remainder are from Jamaica 

 and Cuba. 



Species. 



1. bidentata, Ad. 4. globulosa, Orb. 7. opalina, Ad. 



2. depressa, Orb. 5. linguifera, Jonas. 8. pisum, id. 



3. eolina, Dud. 6. nitida, Gray. 



Figure. 



Proserpina nitida. PI. 21. Pig. 121. Shell, showing the aperture with 

 its tooth-like plaits and simple lip. 



Genus 11. SUCCINEA, Draparnaud. 



Animal ; of large subgelatinous bulk ; head with four stout inflated 

 tentacles, of which the lower pair are very short. 



Shell; ovate, thin, fragile ; spire small; aperture large, with the 

 margins disjoined; columella narroio and thinly edged; lip 

 simple. 



The well-known transparent Amber snail, Succinea putris, of our mud- 

 banks and damp meadows, gives but an inadequate notion of the genus in 



