LAMPREYS AND FISHES OF INDIANA. 169 



skeleton ; and Dr. Jordan says that it almost all disappears in the 

 process of frying. On the other hand, Prof Forbes states (i^, No. 2, 

 68) that it is generally eaten in southern Illinois. While of no value as 

 food, they are quick to bite and full of pluck. Tliey thus furnish sport 

 to the fisherman who fishes for sport and not for filling the frying-pan. 



Dr. Fullel)orn, of Berlin, Germany, has most recently investigated the 

 breeding habits of this fish. In the region about Madison, Wisconsin, 

 the eggs are deposited during the mouths of April and May. In the 

 center of a mass of aquatic vegetation a clear space soiue two feet across 

 and nearly three feet deep would be found, the bottom of which was 

 formed of a fine network of roots and delicate l)ranches. This "nest" 

 had the appearance of having been made by the fish, and in them was 

 frequently found the male On the bottom and sides of this nest the 

 eggs Avere laid in thousands. Each egg has a diameter of about one- 

 twelfth of an inch. The male remains about the nest until the brood is 

 hatched and the young have reached a length of a little more than one- 

 half inch. The brood then follows the male, who remains near shore. 

 About June 1 the adult fishes and the young suddenly disappear, having 

 apparently betaken themselves to deep water. The eggs appear to hatch 

 in from six to fourteen days after deposition. When the young are first 

 hatched they are only about oue fifth inch long. 



Sub class 3. rilYSOSTOMI. 



Primitive skeleton thoroughly os-ified. Membrane bones well devel- 

 oped. Body naked, or covered with scales, which, except in rare cases, 

 are cycloid. Tail, at least to external view, not heterocercal. Fin-rays 

 soft and articulated, exct^pt occasionally oue or two of the most anterior 

 of the dorsal and pectoral. Ventrals, if present, abdominal. Air- 

 bladder, if present, with a duct opening into the alimentary canal. 



The members of this sub-class are, in the last resort, distinguished from 

 the PhysocUdi only by the possession of a duct from the air-bladder to the 

 alimentary canal. The PhysocUdi have, in the great majority of cases, 

 the ventrals either thoracic or jugular; a portion or the whole of the 

 dorsal and anal made up of spines; and the scales are very often ctenoid. 

 Or, if the fins all consist of soft rays, the ventrals are thoracic or jugular. 

 Even the test just given fails in the Scomhere&ocidce; but these do not 

 concern us, they being marine. Any of our fishes which have the dorsal 

 and anal fins composed wholly of soft rays (except occasionally the most 

 anterior one or two) and with the ventrals abdominal belong to the Phys- 

 ostorni. The Physostoml and the PhysocUstl form two great bodies of 



