GAMMA RID^E. 



they are large at the base, the first joint is longer than 

 the other two ; the first two are produced anteriorly to 

 a point upon the upper surface, and notched into a dis- 

 tinct tooth upon the inferior: the flagellum is longer 

 than the peduncle, and the secondary appendage is about 

 half the length of the primary. The inferior antennae have 

 the upper distal extremity of each joint produced into 

 a tooth; the flagellum is not longer than the last joint 

 of the peduncle, and consists of one long articulus, or, 

 more probably, several are fused together, of which the 

 upper margin alone shows any indication of the several 

 joints. The first two pairs of legs are uniform, both in 

 dimensions and shape; the wrist is anteriorly produced 

 along the inferior margin of the hand ; the hand is sub- 

 triangular, tolerably large, having the palm oblique, de- 

 fined by a strong spine situated at the apex of an obtuse 

 angle ; the palm is likewise furnished with short hairs, 

 similarly formed to those on the hand of Liljeborgia 

 pallida. The walking legs are subequal, the two first 

 being rather the shortest ; the thighs of all are remark- 

 ably narrow. The ante- and penultimate pairs of caudal 

 'appendages have the upper margin of the outer branch 

 serrated, being also marked at regular distances by a 

 strong tooth. The ultimate pair are considerably longer 

 than the preceding; the branches are of equal length, 

 having their upper margins very slightly serrated. The 

 middle tail-piece is notched, but to what extent we have 

 not been able to determine. 



This species was taken from a nullipore bank off the 

 coast near Cumbrae, by Mr. David Robertson, who 

 kindly sent it to us. 



It is not improbable that this species may belong to 

 a separate genus from Ph. antiqua, but all the parts of 

 the latter, as far as known, correspond very nearly to 



