186 Mr. R. Templeton's Descriptions of 



rected forwards. Immediately behind these legs arises, from the in- 

 ferior part of each joint, the bifurcate articulated appendages which 

 are called fin-feet ; so that all the rings of the body have either 

 true or fin feet or styles articulated to them, in this respect diflfer- 

 ing from all hitherto noticed genera. 



This species swims with considerable rapidity and has all the 

 habits of our common European marine Gamtnari. Its size is about 

 ^th of an inch, and its colour subject to but little variety, being of 

 a greenish tint more or less brownish in the specimens I have ex- 

 amined. In its generic characters the great and disproportionate 

 length of the 2 last pairs of feet, the fin-feet arising from the suc- 

 ceeding joints, and the appearance presented by the antennae, which 

 are much longer than in the contiguous genera, at once distinguish 

 it. The claws also oflfer distinctions. 



Fig. 1. a, The animal magnified. 



b, The last joint and claw of the 6th pair of legs. 

 The feet of one side only are figured, to prevent misconcep- 

 tion or confusion in the drawing?. 



Thaumalea depilis. Plate XX. fig. 2. 



Erythrocephalns melanophthalmus ? Tilesius, Neue Ann. Wetter- 

 ausch. i. p. 6. pi. xxi. a. fig. 5. 



Body hyaline, with a few dark specks, especially along the edges 

 of the abdominal plates or rings. The head is quadrangulai, not 

 large ; the eyes deeply imbedded in it ; front retracted inferiorly, 

 from about its middle arise the superior antennae, which are short 

 and tumid ; 1st joints short, forming together a truncated cone on 

 which rests the elongate spindle-shaped 4th joint. The inferior an- 

 tennae arise from the inferior part of the frontal surface ; they are 

 much smaller than the superior, composed of 4 joints, of which the 

 1st is small and obconic, the remainder in length subequal, the last 

 conic. The body swells out to about the 5th ring, when it again be- 

 comes gradually reduced in size and ends in a bifurcate articulated 

 tail. There are only 6 legs apparent, the 2 first jiairs being very 

 short and apparently without claws, the 4 posterior pairs of about 

 equal length, tapering, and with slender slightly curved claws. From 

 the abdominal joints proceed bifurcate articulated appendages, but, 

 as well as the whole animal, apparently devoid of hairs. 



This minute species swims but badly, having none of the celerity 

 of motion so conspicuous among the Gammari, to which it bears re- 

 semblance in its form. It differs from every genus I am acquainted 

 with, in the antennae, in the relative dimensions of the legs, the 



