THE ALLIS SHAD 133 



The dorsal fin, placed about in the middle of the 

 length of the fish, is composed of four or five 

 graduated simple and fourteen to eighteen branched 

 rays ; the anal has three simple and twenty to 

 twenty-four branched rays, and its base usually 

 measures about one-fourth of the distance from the 

 head to the caudal fin ; the latter is deeply forked ; 

 the pectorals almost reach the pelvics in the young, 

 but not in the adult, whilst the small pelvics are 

 inserted nearly below the origin of the dorsal. The 

 coloration is silvery, with the back greenish or 

 purplish ; there is usually a dark spot on the 

 shoulder, which is sometimes followed by a series of 

 smaller spots. 



The Allis Shad is found on the Atlantic coasts 

 of Europe and in the western Mediterranean ; it 

 attains a length of about 30 inches, and a weight 

 of 8 lbs. 



In the sea this fish swims probably in small com- 

 panies, feeding especially on little crustaceans, but 

 at times also on the fry of other fishes. In the 

 spring, usually about April, the shoals ascend the 

 rivers, sometimes for enormous distances ; thus in 

 the Rhine they reach Switzerland, and in the Elbe 

 Bohemia ; they also penetrate nearly to the sources of 

 the Seine and Loire. They do not seem to be very 

 plentiful in our rivers except the Severn and the 

 Shannon ; heavy floods or thunderstorms check their 

 ascent, and may even drive them back to the sea ; once 

 well clear of the estuaries and fairly started on their 

 journey they appear to cease feeding and to devote 

 all their energies to pressing on towards their spawn- 

 ing places ; they usually breed in May or a little 

 later (hence the German name MaifiscJi)^ and make 

 10 



