454 APPENDIX TO CRUSTACEA [December, 



Georgia^ and subsequently an individual of the other sex 

 by myself near the same place. 



The pedipalpi are precisely the same as in Pinnothe- 

 res, but this animal seems to be estranged from the ge- 

 nus by several minor characters, as those drawn from the 

 robust fourth pair of feet, the indurated consistence of 

 the body, the transverse tliorax, Sec. In the two latter 

 respects somewhat resembling the following species. 

 From its magnitude, the firmness of its integuments, and 

 the similarity of the sexes, it seems probable that it is 

 not parasitic. Under these considerations I considered 

 it the type of a distinct genus, and had associated with it 

 the following species; but I prefer in this place uniting 

 them under the genus Pinnotheres. 



4. P. monodactylum^. (Male.) Thorax transverse; 

 hands monodactyle. 



Inhabits the American coast. 



Richmond Museum. 



Thorax transversely subeliptical, narrowing each side 

 to the middle of the lateral edge, which is rounded, a 

 tubercle each side marking the situation of the anterior 

 lateral angles, surface punctured; orbits suborbicular; 

 <mtenncs^ exteriores subequal to the breadth of the cly- 

 peus; hand oblong, somewhat quadrate; pabn concave 

 and ciliated in the middle, a spiniform angle instead of a 

 finger, with a tooth at its base, and another at the base of 

 the thumb larger; thumb abruptly incurved at base, rec- 

 tilinear towards the tip, with an angle at the interior mid- 

 dle, tip acute, attaining the tip of the spiniform angle; 

 feet, second, lifth and third pairs subequal, the latter ra- 

 ther larger, fourth pair larger, and wdth the fifth pair 



