ON THE CAUDAL AND ANAL FINS OF GOLD-FISHES. 253 



(Fig. 6, a.p.v.c.) is beset witli two neural spines, a.p.w. and a.^/jii 

 The posterior of these processes is prolonged backward and takes 

 a small share in carrying the fin rays of the dorsal lobe of the 

 tail. The ha3mal spine (a.p./i.) of the same vertebra is thicker 

 and longer than those of preceding ones, and carries at its thickened 

 termination a few of the fin-rays constituting the ventral lobe of 

 the tail. The penultimate centrum (p.v.c.) is beset with one neural 

 and one hcemal spine. Both of them are respectively stronger and 

 larger than the corresponding spines of the preceding vertebra. Each 

 carries a few of the caudal fin rays. From the last recognizable cent- 

 rum (l.v.c.) many processes start out. The uppermost and most 

 anterior of these is a short lancet-shaped piece (/.), which occupies 

 a position similar to that of more anteriorly situated neural spines. 



The; next succeeding process — the urostyle (u.) — consists of a 

 pair of long, styliform plates, running obliquely upward. The two 

 pieces are arranged in the fashion of a razor-sheath and enclose 

 between them the hinder end of the notochord, while the spinal chord 

 runs along their dorsal edge. The urostyle is, in fact, the continua- 

 tion of the vertebral column, representing a certain number of 

 coalesced vertebral bodies. At its distal end is found a pair of free 

 slender bones (h.), one on each side. 



The third process, structurally connected with the last recognis- 

 able centrum, is a flat, dilated bone (e.) which running backward 

 forms an acute angle with the urostyle. Just below the root of the 

 third process (e.) and facing obliquely backward and downward, 

 there is in the last vertebral centrum a depression, to which the fused 

 extremities of two flat bones (/. and g.) are connected by cartilage. 

 The centrum (l.v.c.) may in fact be considered as possessing one 

 neural ( /. ) and three caudal appendages (e, f, g.). 



In the angular space formed by the urostyle ( u.) and the upper- 



