and on Six New Species of C^usfaceay Sfc. 175 



A single specimen was obtained in the Frith of Forth, near 

 Anstruther ; it was found in shallow water, together with a 

 number of other Schizopoda, and, as far as I am aware, is the 

 first instance of a species of this genus got on the British coasts. 



GENUS CYNTHIA, fig. 1., pi. II. 



Subabdominal fins composed of two joints, four last fins with the termi- 

 nal plume double, with an opaque, bifurcate, and convolute organ 

 raising between each. 



C. Flemingii. — Inferior antennal scale almost twice as long as the pe- 

 duncle. A thick fringe of strong hairs bordering its inner edge. Ros- 

 trum slender and finely pointed. Volute organ between the plumose 

 sctse of the subabdominal fins minute ; edges of the middle plate of the 

 tail spined. 



Long, eight lines. Hab. Frith of Forth. 



Description. — The whole body of an opaque straw colour, with the reti- 

 culated portions of the eyes black. Superior antennae with the pe- 

 duncle three-jointed, the two setaceous portions arising from the second 

 joint of the peduncle, the last joint ovate, surrounded with a thick 

 fringe of hairs, these hairs are bent downwards at their extremities, so 

 as to form a concavity on the lower surface. The peduncle is about 

 twice the length of the eyes. The peduncle of the inferior antennae 

 extends to the origin of the setaceous portion of the superior antennae, 

 the two last joints are slender and clavate. A long slender and 

 pointed scale arises from the first joint of the peduncle, above the se- 

 taceous portion ; this is twice as long as the peduncle, and is thickly 

 fringed with long hairs, which are directed inwardly so as to meet 

 those of the opposite side. The carapace is not very large, curved at 

 its posterior edge, and produced at its posterior and inferior angle. 



Abdomen slender, the inferior edge of each segment considerably pro- 

 duced, and all of them but the last bearing a fin composed of two 

 joints ; the first joint is scale-like clavate ; the second is multiarticu- 

 late and plumose, all of them but the first pair double. The bifur- 

 cate convolute organ between the double plumes is very minute. 

 Middle plate of the tail edged with spines on its sides, and entire at 

 the extremity. External caudal-fins twice as long as the middle plate, 

 and curved upwards, the internal one about the same length as the 

 middle plate, and pointed. 



The bifurcate and convolute organ between the double plumes 

 of the four last subabdominal fins, together with the number of 

 joints in these fins, seem to be the most striking characters of 

 this genus. Mr Thompson, in the third memoir of his Zoolo- 

 gical Researches, says, *' It is not in the tuimber of joints alone, 

 however, that they (subabdominal fins) differ, their form and 



