MACROURI. 213 



face. Two pair of the limbs next them are each provided with forceps, 

 which are wanting in the rest. Several thin finny processes, of irregular 

 structure, auxiliary to the animal's motions, also in securing the roe, 

 and for other purposes, belong to the interior of the part between the 

 limbs and the last segment. As two pair pertain to each segment, there 

 are ten pair in all, — each consisting of an oval plate, completely fringed, 

 unless at the root, where the united plates are connected with the ani- 

 mal. But the reader, to understand these obscurities, must rather resort 

 to inspection of the parts than endeavour to discover their structure and 

 use by explanation. 



Two long external antennse originate from beneath the anterior ex- 

 tremity, and between them two others, shorter and forked. 



All consist of numerous vivid, red, cylindrical segments, with inter- 

 annulations. The shorter antennae are of curious structure, and beauti- 

 fully annulated ; the interior of the shorter limb of the fork is fringed 

 by pencils, and some straggling hairs near the upper part. No pencils 

 appear on the other limb of the fork. 



A large black reniform eye, of very peculiar aspect, apparently de- 

 rived from a shelly plate sustaining the one side, rises on each of the 

 sides of the rostrum. 



Many parts of this creature are very finely fringed, the fringe con- 

 sisting of the most luxuriant and beautiful feathers, as exposed by the 

 microscope. The same structure pervades those of the head, those of 

 the abdomen, and those of the caudal extremity ; the pediments sustain- 

 ing the long antennae are fringed by above six;ty such feathers. None of 

 these ornamental borders are displayed, unless by the animal during life. 



The tail itself consists of a central portion, with two moveable foli- 

 aceous plates on each side, thus making up the whole complement of five 

 portions. A lateral fold or joint, with a spine on each side, distinguishes 

 the external plate at a third of the length of each from the fringe. 



Owing to the length of the body this appears a slender animal, and 

 in fact it is so. A specimen extending thirteen inches was only fourteen 

 lines thick. All the parts of those much smaller in size will be found in 

 nearly the same proportion as here specified. The body of one extended 



