266 Roosevelt Wild Life Annals 



says it is easy to distinguish male Tullibees during the spawning time, for then 

 they are smaller and more trim than the females. 



The minnows and suckers are peculiar in that the breeding males, with few 

 exceptions, have horny tubercles or pearl organs on the head or other parts of the 

 body (Fowler, '13, p. 471). In the Blunt-nosed Minnow, the Horned Dace and 

 the Fallfish, the tubercles are very prominent and confined to the head. The Chub 

 Sucker has conspicuous pearl organs on the snout, with many small ones on the 

 anal fin and adjacent part of the body. The Common Sucker and the Common 

 Redhorse have anal fin tubercles, but none on the head or the body, except on a 

 small area adjacent to the anal fin. The Common Sucker has pearl organs on the 

 lower half of the caudal fin, in addition to those on the anal. In the following 

 Oneida Lake species the breeding males have fine granules on the head or the 

 back, instead of prominent and rather definitely localized tubercles : Silvery and 

 Gilbert's Minnows, Silverfin, Common Shiner, Rosy-faced Minnow and Black- 

 nosed Dace. The male Golden Shiner has the sides rough with minute tubercles, 

 but has none on the head (Forbes and Richardson, '09, p. 128). According to 

 Hessel ('81, p. 872), the Carp has wart-like protuberances on the head and back; 

 but these were not found by Cole in his extensive studies of this species in the 

 Great Lakes region (Cole, '05, p. 578). The chief use of these pearl organs, in 

 minnows, according to Reighard ('04, p. 211), is to enable the male to hold the 

 female during the spawning act. But in some species they are of use in combats 

 and in nest building. 



The males of minnows and suckers are often colored very differently from the 

 female during the breeding season. But such difterences are not prominent at 

 other times. Tiu' male Blunt-nosed Minnow becomes almost black. In the male 

 Silverfin a white substance is deposited in some of the fins and the body becomes 

 marked with blue and yellow (Forbes and Richardson, '09, p. 145 I. The male 

 Common Shiner is reddish on the sides and on the fins (I.e.. p. 147). Much red 

 develops also in breeding males of the Rosy-faced Minnow, Horned Dace, Long- 

 nosed Dace, and Redhorse; in fact, the.se males in breeding dress are among the 

 most attractive of our fresh water fishes. In many cases these colors can be seen 

 on fishes in their native waters, but to see the colors well it is an advantage to 

 transfer the fish to an aquarium, although in some cases the colors become 

 decidedly duller after the fish has been caught, or after its sexual excitement has 

 ceased, as Hankinson ("21a, p. 1,^') has observed with the Common Sucker in 

 Illinois. 



The form of the body is sometimes altered in minnows and suckers by the 

 thickening of the tissues of the back, as in the Blunt-nosed Minnow, or of the 

 snout, as in the Silverfin. Male Brook Sticklebacks are also highly pigmented, 

 making them almost the gaudiest of our fresh-water fishes. The males of some 

 darters found in the Eastern United States are exceedingly beautiful little fish, but 

 only one of the highly colored species was taken by us in Oneida Lake, namely, 

 the Tuwa Darter (See Forbes and Richardson, '09, p. 306). 



Young Fish. Some data were obtained cm the habils and haiiitals uf ymmg 

 fish in Oneida Lake, as they occur in shallow water, but very little is known of the 



