436 



MANUAL OF THE MOLLrSCA. 



Shell when young free, equivalve, Anodon-sliaped, -witli a long 

 and prominent ligament, and two adductor impressions ; adult 

 irregular, inequivalve, attached by the right valve ; umbones 

 elongated, progressively filled up with shell, and forming an 

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

 ligament in a marginal groove ; interior pearly, muscular 



Fig. 222. Mulleria lobata, Fer. (Originals) 



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

 attached A^alve, showing the single muscular impression, and 

 projecting spur with the nucleus, consisting of Jo^/i valves of the 

 fry, united, and filled up with shell.* 



Distribution, Eiver Magdalena, near Bogota, Net?" Granada. 



Mr. Isaac Lea has determined the identity of Miilleria 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'brbigny very liberally placed his suite of specimens of this remarkable 

 genus in the British Museum. Oct., 1854. 



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

 collection, was purchased many years ago by Mr. Thomas Norris of Bury, for £20. 



