THE FAMILY NAIADES. 



15 



o 



QUADRATE. 



*lacryinosiis.f Lea. 



*asperrimus.| Lea. 



Uiiio c|Uiidiulus. Say. 



*fragos!US.§ Con. 



Pliillipsii. Con. 



*pustulatus. Lea. 



*Schoolciaftensis. Lea. 

 Unio prasinus. Con. 



TRIANGULAR. 



*apiculatus. Say. 



*asper. Lea. 



*Dorfeuillianus. Lea. 



*stapes. Lea. 



*metanever. Lea. 



Unio metanevra. Raf. 

 Unio nodosiis. Bar. 

 Uniovugosus (Flat). Bar. 

 Unio melanevius. Con. 



TRIANGULAR. 



*coinuliis. Bar. 



Unio reflexa'? Raf. 

 Unio reflexus. Con. 



SUBROTUND. 



*puslulosus. Lea. 



Unio verrucosus. Bar. Var. b. 

 Unio verrucosa. Valen. 

 Unio verrucosus albus. Say; but 

 V i4j)0t of Hildreth.'^ 



*turgidus. Lea. 



Unio Mortoni. Con. 



*Cooperianus. Lea. 



*verrucosus. Bar. Eat. ; 



Unio luberculata? Raf. ~ 



Unio tuberculosa. Valen. '* 



Unio verrucosus purpureus. Hild. 

 Unio tuberculatus. Con. 



*graniferu3. Lea. — 



*nodulosus. Lea. 



My a nodulosa.^ Wood. Dill. 



*irroratus. Lea. Eaton. 



Unio verrucosus albus. Hild. 



inflection on the posterior basal margin. It maybe doubted if this should be considered a plicate shell. I con- 

 sider that the folds of the growth, particularly in the male shells, require it to be placed here. 



t It is a matter of some doubt if this be more than a beautiful variety of asperrimus (nobis). Future ob- 

 servation must determine. Ferussac and some other zoologists believe it to be distinct. Dr Ward says they 

 " are certainly distinct." 



J Mr Say supposed this to be the rugosus, Barnes. Two specimens referred to by Mr B. as rugosus were 

 under my inspection, and proved to be — the one a flat 7netanevra, Rafin., the other a plicatus (Lesueur). Mr 

 B. in his reclamation recognises his rugosus as U. Peruviana, Lam., which shell is undoubtedly the plicatus, 

 (Lesueur and Say). 



§ This shell has been considered the female of asperrimus (nobis), but I am, after the examination of 

 many specimens, disposed to think it to be distinct. Some of our best western naturalists think it to be the true 

 rugosus of Barnes. 



II A specimen sent to me by Dr Hildreth as Unio verrucosus albus, proved to be a true irroratus (nobis). 



% This shell, as figured by Wood in his " General Conchology," seems to me to be distinct from the pus- 

 tulosus (nobis), with which it has been confounded. The figure of Wood is longer than any pustulosus I have 

 seen, and the epidermis is much darker (" bottle green"). The nodules are more numerous about the beaks, and 

 the lateral tooth is longer and thicker. I doubt if the nodulosus be an American species. 



