(51) 
144. N. exilis , sp. nov. Slender Cat. Rare. Three specimens were 
obtained in McLean county by Prof. Forbes, the only ones seen. These 
specimens present the following characteristics : 
Head in length 4i ; depth 6^ in length. Eye 4 f in head. Dorsal I, 
6; Anal 1, 5. Ventrals 8 or 9. Inter orbital space 3i in length of head. 
Dorsal a trifle nearer snout than anal. From snout to dorsal 3} in total 
length. Dorsal as high as long, and If in head. Dorsal spine small, 3i in 
head. Pectoral spine 2\ in head Width of head 1£ in length ; depth 2| 
in length of head. Base of anal 1^ in head. 
FAMILY ANGUILLIDAE. 
Genus Anguilla , Thunb. 
145. A. vulgaris , var. rostrata, (LeS.) Nelson. Common Eel. Occurs 
in Lake Michigan and most of the larger streams through the state, but is 
far from common anywhere. 
FAMILY AMILDAE. 
Genus Amia , Linn. 
146. A. calva, L. Dog Fish. Abundant throughout the state. 
FAMILY LEPIDOSTEIDAE. 
Genus Lepidosteus , Lac. 
147. L. osseus , (A.) Ag. Gar Pike. This is far the most common 
species in Lake Michigan and the Calumet river, where it is very abundant. 
It also occurs throughout the state. 
148. L. platystomus, Raf. Short-nosed Gar. Occurs through- 
out the state, but is much more abundant in Illinois and south. 
Genus Litholepis , Raf. 
149. L. adama,nteus , Raf. Alligator Gar. Common in the Ohio 
and Mississippi rivers, occasionally straying up smaller rivers into the in- 
terior of the state. 
FAMILY POLYODONTIDAE. 
Genus Polyodon , Lac. 
150. P. folium , Lac. Duck-billed Cat. Common in central and 
southern Illinois in the larger streams. Rare in the northern part of the 
state. 
FAMILY ACIPENSERIDAE. 
Genus Acipenser , Linn. 
151. A. maculosus , LeS. Sturgeon. Very abundant in Lake Mich- 
igan and the larger rivers throughout the state. 
152. A. rubicundus , LeS. Lake Sturgeon Very common in Lake 
Michigan, ascending Calumet river in winter. 
Genus Scaphirhynchops , Gill. 
153. S. platyrhynchus , ( Raf 1) Gill. Shovel-nosed Sturgeon. Com- 
mon in the southern part of the state in the Ohio and Mississippi rivers. 
