i8i8.] <5F THECNITED STATE'S^. ^/^ 



Joiut eacli witli a ferraginous spot above, fct joint of 

 each pair, with a green spot on the inner side ; feel^ 

 hairy, faintly spotted with green, fifth and sixth pair& 

 j^enerally reflected above the back, seventh pair re- 

 Aecied when sAvimming ; three last segments of the 

 body composing the tail, each witli three fascicles of 

 short spines above ^ ejjes marginal, smaller above i 

 hands oval, palm unarmed. 



Length not quite half an inch. 



This species is a common inhabitant of our rivers^ 

 and is frequently introduced into Fhiladeiphia, in the 

 Bchuylkill water; an individual placed in a glass of 

 water, swam nimbly about sometimes upon bis baclc^ 

 the superior antennae being projected forwards, and 

 tiie inferior pair decurved j- when at rest it was placed. 

 en its side, with the body incurved 5 it was not very 

 partieulai' in ilm choice of food, it tore out of the shel^ 

 and eagerly devoured, a young Lymncea cai^scopium^ 

 and also eat some vegeta])le food. The antepnje ^is- 

 sists these animals very much in obtaining the miunte. 

 paJpiicles of food, which abound in the vratei ; whetjur 

 ail object of a proper size coiaes witiun a moderate 

 distance of his naouth, one of them strikes it w ith erreat 

 dexterity into the grasp of the four anterior feet, ih(^ 

 first pair of Vv idch appears to be most employed. It 

 dilfers from the G. j) ill ex of Europe, more especiailj 

 rn having reniform eyes. An e:*^traordiuQ,ry resemn 

 Mance prevails, between this species au^ an inhabK^ 

 taut of the salt water, tiwi only difference appears tQ^ 

 he in the somrwhat Iti^-ger size ^f the Lvtar, but not 

 Aaring succeeded in di*Pt»>e'ing a f^peqiSc f|!J®'ren|^ 



