180 DEEP SEA FISHES. 
them all lie between 37.3 and 40 degrees Fahrenheit, averaging about 38.8 
degrees. The variation in the temperatures of the different stations is 
remarkably small but that in the pressures at the widely different depths 
is enormous. 
GADIDE. 
MIcROLEPIDIUM gen. n. 
Form more compressed, deeper and more massive in the forward half 
than that of Lepidion, tapering to very slender backward; body cavity less 
than half of the total; body and head covered with small scales. Mouth 
large, oblique, lower jaw longer. Teeth in villiform bands on the jaws, 
stronger and in a V-shaped single series on the vomer, none on the palatines. 
Eyes large, lateral. Branchiostegal rays seven. Gills four, a slit behind 
the fourth; rakers numerous, long, slender, Gill openings wide ; membranes 
united, free from the isthmus. Pseudobranchizx present. No barbel. Two 
dorsal fins; anterior small, of eight rays. One anal fin; caudal narrow, 
distinct ; pectorals small, elongate; ventrals long, narrow, apparently of a 
single bifid ray, but really of two rays closely bound together and with 
rudiments of a couple of others. Pyloric ceca. 
Microlepidium differs from Lepidion in having the lower jaw longer than 
the upper, in having a longer first dorsal of eight rays instead of four, in 
having the dorsals hardly separated, in having ventrals of four rays instead 
of six, in having a less distinct lateral line, and in having a much larger 
number of pyloric appendages. 
Of the two known species of this genus, one, IZ. verecundum, Lepidion vere- 
eundum, Gilb., 1896, P. U. S. Mus., 456, has the maxillary reaching to below 
the front of the pupil, “ astiffish pointed projection representing the barbel” 
on the end of the lower jaw, no spines on snout or opercles, ventrals half as 
long and pectorals about half as long as the head, an anal of thirty-seven rays 
and deeply notched behind the middle, and has about seventy-five scales in a 
longitudinal series ; while that described below has the maxillary subtending 
more than half of the eye, has no projection on the chin, has a moderately 
strong spine on the operculum, has ventrals a little longer than the head, 
has pectorals more than two-thirds as long as the head, has an anal of forty 
rays hardly notched near the middle, and has about one hundred and four 
teen scales in a longitudinal series. JL. verecundum was obtained by the 
“ Albatross,” near the Revilla Gigedos, off the Coast of Mexico, in a depth 
of 364 fathoms 
