EMBODY] THE HORNED DACE 169 



have spines on either side of the head and a red coloration on the 

 belly. The most distinctive mark is the black spot or blotch 

 situated at the base and front part of the dorsal fin. By this spot 

 the chub may be known from all other brook minnows. 



Breeding Habits 



Fishes may be divided into two groups, nest builders and non- 

 nest builders. The nest builders are also of two kinds, (i) those 

 giving personal care and protection to eggs and young and (2) those 

 deserting nests soon after the eggs have been deposited. The chub 

 belongs to the second class of the nest builders. 



The breeding season varies with the temperature of the water 

 and thus may occur earlier in the southern than in the northern 

 states. In the latitude of New York State the chub usually begins 

 about the first of May and continues well into June. If one visits 

 a stream during this time he may observe in shallow rapid places 

 elongated patches of clean gravel which stand out prominently 

 from the remainder of the silt and slime-covered bottom. 



Closer examination will show that these patches are ridges of 

 gravel ending down-streamward in a slight excavation which in 

 turn is followed by a roughly angular shaped area of sand. The 

 ridge may be two to three inches deep and as wide as the ridge. 

 This whole structure is the work of the male chub alone. Accord- 

 ing to Professor Reighard, the chub begins to excavate a cavity on 

 the level both by pushing the larger stones up stream and carrying 

 the smaller ones in his mouth. As he works the former cavity is 

 not only filled but the stones are heaped above the bottom. In 

 this manner he continues to excavate and refill always working 

 down stream. The cavity at the end represents the place where 

 the male stopped working and the sandy area below is the fine 

 material dug up by the fish and carried down stream by the water 

 current. 



During its construction the nest is guarded by the builder. 

 Often fighting takes place between two males at which time the 

 "horns" on the front of the head are used as weapons. It is stated 

 by Professor Reighard that the female does not deposit all of the 

 eggs at one time but may return repeatedly to the same nest or 

 even to one occupied by another inale. Thus a chub nest may 

 contain eggs from several different females. 



After each successive spawning the male begins again to excavate 

 with the result that the stone ridge is lengthened and the deposited 



