543 



eight per cent. — while eight out of our seventeen sunfishes {Centrar- 

 chinac ) have been taken tacrc. Next. ])erhaps, one searching the 

 pebbly beaches or scanning the weedy tracts will be struck by the small 

 number of minnows or cyprinoids which catch the eye or come out in 

 the net. Of our thirty-three Illinois cyprinoids, only six occur there — 

 about eighteen per cent. — and only three of these are common. These 

 are in part replaced by shoals of the beautiful little silversides {Labidcs- 

 thes sicculus) , a spiny-finned fish, bright, slender, active, and voracious 

 — as well suppliel with teeth as a perch, and far better equipped for 

 self-defense than the soft-bodied and toothless cyprinoids. Next we note 

 that of our twelve catfishes (Sihiridae) only two have been taken in 

 these lakes — one the common bullhead {Ictaliinis nebulosus), which 

 occurs everywhere, and the other an insignificant stone cat, not as 

 long as one's thumb. The suckers, also, are much less abundant in 

 this region than farther south, the buffalo fishes' not appearing at all in 

 our collections. Their family is represented by worthless carp" by two 

 redhorse'', by the chub sucker'' and the common sucker {Catostomus 

 teres), and by one other species. Even the hickory shad^ — an ich- 

 thyological weed in the Illinois — we have not found in these lakes at all. 

 The sheepshead'^, so common here, is also conspicuous there by its ab- 

 sence. The yellow bass', not rare in this river, we should not expect in 

 these lakes because it is, rather, a southern species ; but why the 

 white bass*, abundant here, in Lake Michigan, and in the Wisconsin 

 lakes, should be wholly absent from the lakes of the Illinois plateau, I 

 am unable to imagine. If it occurs there at all, it must be rare, as I 

 could neither find nor hear of it. 



A characteristic, abundant, and attractive little fish is the log perch 

 (Pcrcina caprodcs) — the largest of the darters, slender, active, barred 

 like a zebra, spending much of its time in chase of Entomostraca among 

 the water plants, or prying curiously about among the stones for minute 

 insect larvje. Six darters in all ( litlicostoniatinae), out of the eighteen 

 from the state, are on our list from these lakes. The two black bass" 

 are the most popular game fishes — the large-mouthed species being much 

 the most abundant. The pickerels'", gar", and dogfish'" are there about 

 as here; but the shovel-fish'^ does not occur. 



Of the peculiar fish fauna of Lake Michigan — the burbot'*, white 

 fish," trout,"' lake herring or cisco," etc., not one species occurs in 

 these smaller lakes, and all attempts to transfer any of them have failed 

 completely. The cisco is a notable fish of Geneva Lake, Wisconsin, but 

 does not reach Illinois except in Lake Michigan. It is useless to at- 

 tempt to introduce it, because the deeper areas of the interior lakes 

 are too limited to give it sufificient range of cool water in midsummer. 



In short, the fishes of these lakes are substantially those of their 



'Ictiobus bubalus. 'Ictiobus cyprinus. "Moxostoma aurcolum and M. macro- 

 Icpldotum. 'Erlniyzon sucetta. 'Dorosoma ccpedlanum. "Haploidonotus. 'Roccus 

 interruptus. "Roccus chrysops. "Micropterus. "Esox. "Ki'pldostcus. "Amia. 

 "Polyodon. "Lota. "CoreRonus dupelformls. '"Salvellnus namaycush. 



"Coregonus artedi. 



