436 



MANUAL OF THE MOLLUSCA. 



Shell -when young free, equivalve, Anocion-shaped, witli a long 

 and prominent ligament, and two adductor impressions ; adult 

 irregular, inequivalve, attacliod by the right valve ; umbones 

 elongated, progressively jfilled up "with shell, and forming an 

 irregular " talon " in front of the fixed valve ; epidermis thick; 

 ligament in a marginal groove ; interior pearly, muscular 



Fig. 222. MuUeria lohata, Fer. (Original) 



impressions single, posterior. Fig. 222 represents the left, or 

 attached valve, showing the single muscular impression, and 

 projecting spur with the nucleus, consisting of loth valves of the 

 fry, united, and filled up with shell.* 



Distribution, Eiver Magdalena, near Bogota, New Granada. 



Mr. Isaac Lea has determined the identity of Millleria and 

 Acostoea by examination of Ferussac's type, and the suite of 

 specimens, of different ages, in the collection of M. D'Orbigny.f 



Section B. — Siphonida. 

 Animal with respiratory siphons ; mantle-lobes more or less 

 united. 



a. Siphons short, pallial line simple; Integro-pallialia. 



* M. D'Orbigny very liberally placed his suite of specimens of this remarkable 

 genus in the British Museum. Oct., 1854. 



t The only specimen of Miilleriain England, prior to the acquisition of the D'Orbigny 

 collection, was piu-chased many years ago by Mr. Tliomaa Non-is of Bury, for ii20. 



