PHASIAXELLA. 339 



increasing turns, the outer edges of which are raised and keel- 

 like. L. 0-35. B. 0-25. 



Yar. ohlonga. Narrower, with the spire more protruded. 



Habitat : Common in the lower part of the littoral 

 and upper part of the laminarian zones, in the Channel 

 IsleSj south and west of England, Bristol Channel, St. 

 George^ s Channel^ and on the coasts of Ireland ; Oban 

 and Mull (J. Gr. J. and Bedford) ; Stonehaven^ Aber- 

 deen, and Cruden (Macgillivray); Dunnet bay, Caith- 

 ness (Gordon). I found the variety at Lulw^orth; it 

 may be the male. This species has been noticed by Mr. 

 James Smith as fossil in Ireland, and by Philippi as 

 occurring in the Sicilian tertiaries. It has essentiallj 

 a southern range, extending on the east to the ^Egean 

 and on the west to the Canaries ; Black Sea (Midden- 

 dorff) . Forbes records it as living in the Archipelago 

 from 2 to no less than 80 f., and M*^ Andrew has enu- 

 merated diiFerent depths from 3 to 60 f. 



P. pulla is usually found on Chondrus crispiis ; Mr. 

 Templer says that it feeds on C. mammillosus. Mr. 

 Clark, however, found in the stomachs of all the 

 individuals' examined by him a number of minute 

 Foraminifera, including Truncatulina lobatula and 

 Textularia variabilis, which were entire, and did not 

 appear to have been acted on by the tongue of the 

 Phasianella. He has observed that the animal " is 

 sometimes infested with a longish, strong, cylindrical, 

 dark-brown parasite with a clavate termination, which 

 hangs to the side of the opercular lobe, and may be 

 mistaken for a vibraculum.^^ Its mode of locomotion is 

 like the amble of a horse. The foot being divided in the 

 middle, each side advances in its turn, the stationary half 

 serving as a point d'appui. This shows its affinity to the 

 Littorina family, many of which have the same peculiaritv 



q2 



