90 TELEOSTEI : APODES. — XV, 
ing; teeth small, subequal, in bands on jaws and vomer ; pterygoid 
bones slender; tongue free in front; nostrils lateral; lips full; 
opercles developed; vertical fins confluent; D. beginning well be- 
hind head; P. present; gill openings moderate. Sexual organs in- 
conspicuous. One genus with four or more species, crawling in the 
mud and ooze of brackish and fresh waters of most regions, absent 
on the Pacific coast of America. They are among the most vora- 
cious of fishes. “On their hunting excursions, they overturn alike 
huge and small stones, beneath which they find species of shrimp 
and eray-fish, of which they are excessively fond. Their noses are 
poked into every imaginable hole in their search for food, to the 
terror of innumerable small fishes.” (W. H. Ballou.) 
The eels often move for a considerable distance on land, in damp 
grass. High waterfalls, dams, and other obstructions are often 
passed in this way. It is thought that eels spawn only in the 
sea, and that the female spawns once and then dies. The females 
are larger than the males, paler in color, with smaller eyes and 
higher fins. 
95. ANGUILLA Thunberg. 
218. A. anguilla (L.). Err. Brown, more or less tinged with 
yellowish. Head 84. L. 40. N. Atlantic, from Maine to Brazil, 
ascending all streams; found throughout Mississippi valley, never 
in the open sea. The American Eel (var. rostrata Le Sueur) has 
the distance from front of D. to front of A. a little less than head; 
in the European form this is a little greater, the D. being a little 
farther back in the former. (Eu.) (Lat., eel.) 
Famity XLI. HCHELIDAS. (THe Concer EEts.) 
Eels closely related to the Angquillide, but without scales, and 
with the ovaries in the female evident, and with comparatively 
large eggs similar to those of fishes generally. D. commencing not 
far behind head. Genera 3 or 4; species about 10, all strictly 
marine. Leptocephalus morrisi Gmelin, a translucent, ribbon-shaped 
creature, with very small head, and no generative organs, is occa- 
sionally taken on our coasts. ‘This is thought to be a stage of ar- 
rested development of the young of Echelus, a larval form which 
goes on increasing in size without ever reaching the characters of 
the perfect animal. 
a. Jaws with an outer series of close-set teeth; lower jaw not projecting; dor- 
sal beginning behind root of pectoral. . . . . . . EcHELUS, 96. 
96. ECHELUS! Rafinesque. (€yyeAus, eel, softened into 
Echelus.) 
1 In strictness, the name Leptocephalus should supersede Echelus, but there may be 
some doubt as to the identification of L. morrisi, and for the last hundred years Lepto- 
cephalus has been used as a general name for these peculiar immature forms. 
