LEUCISCUS RUTILTTS. 145 



The ventral fins in the male extend over the vent to the first ray of the anal 

 fin, but in females they are shorter, and do not reach to the vent. The 

 pectoral fins also are more developed in the males. At spawning-.time the 

 females have a fleshy thickening at the base of the dorsal fin, and the anterior 

 half of the base of the anal fin becomes similarly thickened with fatty pads. 

 The terminal rays of the caudal fin are not longer than the rays of the dorsal. 

 The scales are soft, easily detached, marked with close-set concentric rings, 

 and free from radiating rays. They have a firmer consistence in the males. 

 At spawning-time the scales in the female are, to a large extent, wanting, 

 especially on the back ; but even when all the scales are present they never 



.EVCISCUS Ansi-EKSIS (HErKEl,). 



overlap each other at the sides, and are only just in contact. In character the 

 scales closely resemble those of Parapltoxinits alepidotiift. 



The abdomen is the only part of the body which is not spotted with 

 dai'k brown pigment. The spots often run into each other, forming a net- 

 work, and this maybe seen on the caudal and dorsal fins, and sometimes on the 

 anal. The pectoral and ventral fins are always colourless. 



At spawning-time the region round the vent is much swollen in the 

 females, and behind the vent there is a reddish prominence. 



The length varies from two to four inches ; and the small size is one of the 

 most constant distinguishing characters of this species. 



Leuciscus rutilns (Lin.). — The Roach. 



above 7 — 8 

 D. 13—14, A. 12—14, V. 10, P. 16, C. 19. Scales : lat. line 42— 44 



below 5|. 



The Roach (Fig. 73) has the body somewhat elevated, being about as high 



as the head is long, while the head is between one-sixth and one-fifth of the 



length. This fish resembles the Rudd in the deep, compressed form of body ; 



and in some parts of Germany the same name is applied indifPerently to both. 



10 



