NATURAL SCIENCES OP PHILADELPHIA. 243 



fingers; lower indentation deep; snrfaces sulcated, uneven; margins 

 of the fingers beset with long hairs; movable finger considerably 

 hooked at extremity ; smaller hand cylindrical and regular ; fingers 

 longer than palmar portion of the hand ; inner edges of approxi- 

 mated borders pubescent ; no spines on arm. Feet of second 

 pair but little longer than third ; first joint of carpus as long as 

 second and third, and little longer than third, fourth, and fifth ; 

 fifth not as long as third and fourth, and shorter than hand ; 

 third article of following pairs of legs devoid of spine at inferior 

 apex. 



Length, 1.5 inch. 



Family PEN^ID.^. 

 Panaeus occidentalis, nov. sp. 



Rostrum longer than the lamelliform appendages of the outer 

 antennas, recurved, pointed at extremitj'. In the examination of 

 a number of specimens the majority presented ten teeth on the 

 superior margin of the rostrum, and four on the inferior; may 

 vary from eight to eleven on the upper, and from four to five on 

 the lower border. Carapax carinated almost to posterior edge ; 

 sulcus on each side of rostrum terminating about midwa}'^ the 

 carapax ; spine situated on lateral portion near anterior border, 

 opposite the insertion of superior antennae ; ridge running from 

 this spine obliquely downward and backward; second spine be- 

 hind, and on a lower level than the first, and separated fi'om it by 

 a sulcus ; two smaller sulci forming tvvo sides of a triangle around 

 base of second spine. Eye large and rounded ; sulcus on external 

 border of peduncle. Flagella of superior antennae usually shorter 

 than antennary peduncle (in one large specimen the}' were longer). 

 Bases of two first pairs of legs armed with three spines — two on 

 first pair, and one on second ; terminal segment of abdomen sul- 

 cated, pointed, devoid of lateral spines; penultimate and ante- 

 penultimate segments carinated — the ridge commencing on the 

 segment before the antepenultimate, and terminating at the end 

 of penultimate in an acute spine. Length of large specimen five 

 inches. 



The greatest aflfinities of this species are with r.indicus, Edvv. 



18T1.] 



