LANCELET. 419 



distinct line. The anal fin has these rays also, but they 

 become shorter and then disappear, in both the dorsal and anal 

 fin, at about one fifth of the whole length from the tail; beyond 

 which the structure of these fins is simple membrane, as in 

 the corresponding part in the Lamprey; but wider above and 

 below as they approach the tail, and ending at last in a 

 lengthened point. 



In the larger example I was able to discern a structure in 

 these fin-rays which appeared extraordinary; since they did 

 not rise from a single root, as in most fishes, but in the form 

 of a transverse arch, in which the curve formed the support 

 of the fin, while its pillars rest on what may be two transverse 

 spinal processes. The rays of the fin are but little raised or 

 depressed, and when not much expanded the fin appears as 

 thick to the extent of these rays. The vent is at the length 

 of one third of the body from the tail, which is to be especially 

 noted on account of what will be observed presently of what 

 may be supposed another species; and close behind the vent 

 the anal fin begins; but further forward, and along the belly, 

 is a fin or fold without rays, which stretches almost to the 

 throat. The abdominal cavity is long and narrow, and in the 

 first-discovered example when alive there could be "seen a row 

 through its length of small round grains; which were not seen 

 in others after death. There was a tinge of yellowish colour 

 on the body when alive, with tinted reflections of green and 

 yellow near the tail. 



Several eminent anatomists have employed their ingenuity in 

 dissecting this remarkable little fish; but we can only refer 

 briefly to the descriptions they have given us. With the 

 appearance of separate joints in the backbone, Professor Owen 

 says that this entire column consists only of the gelatino-cellular 

 chord and its membranous sheath; and from what we have 

 termed the brain the fifth nerve distributes fine threads to the 

 head, opening of the mouth, and the filaments that belong to 

 it; thus supplying those parts with quick sensation; but the fish 

 does not appear to be endowed with what are termed organs 

 of special sense; although there appear to be parts within the 

 cavity of the mouth that are capable of the sense of taste. 

 The filaments at the mouth appear to be organs of prehension, 

 to convey the food to the entrance of the gullet. It is said 



