UNIO. 



H 



y. 



i 



WIDE. 



Novso ITollandiso. Gray. Han. 



*cylindricus. Say. Sh. & Eat. Ilild. 



Han. Sivain. Chenu. 

 Unio naviformis. Lam. Slain. 



Valen. Desk. 1 

 Mya cylindrica. Eat. 



TRIANGULAR. 



*spinosus. Lea. Chenu. Han. 

 Canthyria spinosa. Swain. 



*collinus. Con. 



QUADRATE. 



*Wymanii. t Lea. 

 Aveia. Ben. 



TRIANGULAR. 



*Kraussii. 3 Lea. 



Castalia sulcata. Krauss. 



*rubidus. Lea. 

 *negatus. Lea. 

 *Averyi. Lea. 

 *encarpus. Lea. 

 *Gabbianus. Lea. 



*Granadensis. Lea. 



*Estabrookianus. Lea. 

 Unio striatissimus. Antli. 



TRIANGULAR. 



*Nicaraguensis. 4 Lea. 

 *planior. Lea. 

 *rugososulcatus. Lea. 

 *Meredithii. Lea. 



OVAL. 

 *stramineus. Con. Han. 



*Gerhardtii. Lea. 

 *aratus. Lea. 

 *Dysonii. Lea. 

 *Caldwellii. Lea. 

 *tripartitus. Lea. 

 *Kowellii. Lea. 

 melleus. Lea. 

 *Paramattensis. Lea. 

 *effulgens. Lea. 

 *vittatuS. Lea. 

 *Syriacus. Lea. 



OBLONG. 



*Scamnatus. 4 More. 



Unio Grundlachi. Dunk. 



1 Deshayes, in Endij. Melh. Vers., torn. ii. p. 580, No. 5. 



* Von Martens considers Wymanii to be a synonym to delodontus, Lam.; but, on a re-examination of 

 the specimens, I am surprised at his conclusion. 



" Dr. Dunker, at Cassel, gave me a shell under the name of Castalia sulrdta Krauss, from Surinam. 

 But it is not a Prisodon (Castalia); for, although it has the outline and general appearance, the teeth aro 

 not striate, but granulate. It therefore belongs to the triangular Unioncs^ and the name of Oiio sulcata 

 being preoccupied it must be changed, which I do to that of the able discoverer. I'mf. Krauss / 

 ErauKsii. This species has remarkable transverse furrows like some of the species of Cyrcna. 



4 Lake Nicaragua, C. A. 



s This very distinct and interesting species is from Caeajagicara River and Taco-taco River, Cuba. 

 It is covered with transverse furrows. 



