GASTEROPODA. 211 



the anterior canal. Lingual teeth {S. floridus) 7 cusped ; uncini, 

 1 tri-dentate, 2, 3 claw-shaped, simple (Fig. 77).* 



Fig. 77. Stromhus. (Wilton). 



Stromhus (floridus) is described by Loven as having a non- 

 retractile, produced muzzle, like Aporrhais. S. gihherulus is 

 represented by Dr. Bergh with all the uncini denticulated. 



Distribution, 65 species. "West Indies, Mediterranean, Ecd 

 Sea, India, Mauritius, China, New Zealand, Pacific, West 

 America. On reefs, at low water, and ranging to 10 fathoms. 



Fossil, cretaceous species; 3 species Miocene — . South 

 Europe. There is a group of small shells in the eocene tertiary 

 strata of England and France, nearly related to the living 

 S. fissurellus, L., some of which have been placed with rosteU 

 laria, because the notch in the outer lip is small or obsolete. 

 They probably constitute a sub-genu«, to which the name 

 Rimella Ag., might be applied. Example, S. Bartonensis. PI. 

 IV., Fig. 2. 



The fountain-shell of the West Indies, S. gigas, L., is one of 

 the largest living shells, weighing sometimes four or five pounds ; 

 its apex and spines are filled up with solid shell as it becomes 

 old. Immense quantities are annually imported from the 

 Bahamas for the manufacture of cameos, and for the porcelain 

 works; 300,000 were brought to Liverpool alone in the year 

 1850. (Mr. Archer.) 



Pteroceras, Lam. Scorpion shell. 



Etymology, pteron, a wing, and ceras, a horn. 



Type, P. lambis. PL IV., Fig. 3. 



Shell like strombus when young ; outer lip of the adult pro- 

 duced into several long claws, one of them close to the spire, 

 and forming a posterior canal. 



Distribution, 12 species. India, China. 



* The lingual dentition of strombus resembles that of aporrhats, and is unlike that 

 of the whelks ; but it is more probable that aporrhais is the representative of strombus 

 than that it is very closely allied. 



