uxro. 



02 



Y. 

 C 

 2 



OBLONG. 



Mexicanus. 



PhiU. 



*ampullaceus. Lea. 



*mutabilis. Lea. 



*2Ethiops. Zea. 



*auratus. Swain. 

 Niaa aurata. Swain. 

 Unio dbtusa. 1 Per. 2 

 Unio depressus. D'Orb. 

 Unio Chiloensis. Phili? 

 Unio Gassiesii. Grat. 

 Unio fragilis. Swain. 



*atratus. Sow. Han. 

 Niaa atrata. Strain. 

 Niaa fragilis. Swa in. 

 Unio auratus. PhiU. 

 Unio Ghilensis. Gray. 

 Unio Molinse. PhiU. 



*lepidior. 4 Lea. 

 Unio lejaidus. Lea. 



*Casablancse. Pit Hi. 5 



*Araucauus. PhiU. 



*confertus. Lea. Han. 



u. 



*l0gubris. Lea. Han. 

 *piceus. Lea. 



I 



OBLONG. 



*insulsus. Lea. 



*obnubilus. Lea. 

 *Greddingsianus. Lea. Chenu. 

 *similis. Lea. 

 *tetricus. Lea. 

 -"Wliiteianus. Lea. 

 *Kullethensis. Lea. 

 *Mardiaensis. Lea. 

 *fuliginosus. Lea. 

 *paliatus. RaveneVs Letter. 

 *Strebelii. Lea. 

 *camelopardilis. Lea. 

 *Tuomeyi. Lea. 

 *Chathameiisis. Lea. 

 *tortivus. Lea. Chenu. 

 *purpurellus. Lea. 

 occidentalis. Con. 



"Watereensis. Lea. 

 Unio Raveneli* Con. 



1 Fide D'Orbigny, Mag. de Zoology, 1835. 



2 D'Orbignj' says this is the depressus of Lesson, and figured and described by Lesson in the Voyage 

 de la Coquille. Now the description of Lamarck answers to the figure of Lesson, and I am disposed to 

 think that the two are the same. I do not know where Ferussac described obtuso. 



3 A specimen of U. auratus from Chiloe, South America, sent to me by Dr. Yandembusch from 

 Bremen, was labelled U. Chiloensis, Philippi. 



4 Lepidus being preoccupied by Dr. Gould for a Florida species, I propose lepidior for my species. 



5 An authentic specimen was given to me by Dr. Dunker in Cassel, and although very close to atratus, 

 I think it will prove to be a distinct species. 



e Prof. Ravenel's name being previously used for a Unio (Amer. Phil. Soc. Trans., vol. v.), it becomes 

 necessary to change Mr. Conrad's name, which I do, to that of the river in which it was found. 



' 14: 



