UNIO. 



OBLONG. 



Mexicanus. 



Phili. 



*ampullaceus. Lea. 



*niutabilis. Lea. 



*JEtliiops. Lea. 



*auratus. Swain. 

 Nida aurata. Sioain. 

 Unio obtusa.^ Fer? 

 JJnio depressus. D^Orb. 

 Unio Ghihensis. Phili.^ 

 Unio Gassiesii. Grat. 

 Unio fragilis. Swain. 



*atratus. Soiu. Han. 

 Alicia atrata. Swain. 

 Nida fragilis. Sivain. 

 Unio auratus. Phili. 

 Unio Ohilensis. Gray. 

 Unio Molinse. Phili. 



*lepiclior.'* Lea. 

 Unio lepidus. Lea. 



*Casablanc£e. Phili.^ 



*Araucanus. Phili. 



*confertiis. Lea. Han. 



*legul)ris. Lea. Han. 



*piceus. Lea. 



OBLONG. 



*msulsus. Lea. 



*obnubilus. Lea. 



*GedcIiiigsianus. Lea. Chenu. 



*similis. Lea. 



*tetricus. Lea. 



^Whiteianus. Lea. 



*Kullet]iensis. Lea. 



*MarcImensis. Lea. 



*fuligmosus. Lea. 



*paliatus. RaveneVs Letter. 



*Strebelii. Lea. 



*camelopardilis. Lea. 



*Tuonieyi. Lea. 



""Chatbamensis. Lea. 



*tortivus. Lea. Chenu. 



*purpurellus. Lea. 



occidentalis. Con. 



Watereensis. Lea. 

 Unio Raveneli.^ Con. 



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



== D'Orbigny 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 tliat the two are the same. I do not know where rerussac described obtusa. 



^ A specimen of U. auratus from C'hiloe, South America, sent to me by Dr. Vandembusch from 

 Bremen, was labelled U. Chiloensis, Philippi. 



" * Lejndus being preoccupied by Dr. Gould for a Florida species, I propose lejndior for my species. 



^ 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. 



" Prof. Ravenel's name being previously used for a U7iio (Amer. Phil. Sac. 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 



