1000 FISHES—GASTEROSTEIDA. 
long and slender caudal peduncle, which is much depressed and strongly keeled, broader 
than deep; no dermal plates; plates of the skeleton not all covered by skin; post 
pectoral plate well developed, striated ; head shortish, the snout rather blunt; thoracic 
processes well developed, widely divergent, forming a V-shaped figure; dorsal spines 
moderate, the anterior diverging to the right or left at different angles, the posterior 
more nearly erect; anal spine large, larger than the dorsal spines; innominate bone 
feeble, lanceolate, not carinated, its edges raised; ventral spines moderate, serrulate, 
length more than one-third that of head ; gill rakers long and slender; gill membranes 
posteriorly free from the isthmus; head 4; depth 53; D. IX-I,9; A.I, 8. Length 24 
inches. 
Habitat, northern parts of Europe and North America, widely distributed, inhabiting 
both salt and fresh waters. It is found in rather deep water in the Upper Great Lakes, 
and northward to the Saskatchawan, and doubtless beyond. It has not yet been ob- 
served in Lake Erie. 
I have compared numerous specimens of the lake form (var. nebulosus), 
sent me by Dr. P. R. Hoy, from Racine, Wisconsin, with examples of the 
common marine form of G. pungitvus, and I find no constant difference 
Dr. Bean finds also no difference between the marine form found in 
America (occidentalis) and the common G. pungitius of Europe. 
The habits of the lake form have necessarily become somewhat changed 
from those of its marine relatives. 
Diagnosis.—This species may be known at once from all other little 
fishes found in our fresh waters by the presence of about ten spines in 
its dorsal fin, arranged in a zigzag row, and entirely disconnected from 
each other. 
Habits.—Little distinctive is known of its habits. It has thus far been 
found in rather deep water in Lakes Michigan and Superior, and, al- 
though not generally common, it may sometimes be found in considerable 
numbers. It is a most active and gracefui little fish, and with it we 
close our series of the Fishes of Ohio. 
