MYCTOPHOIDS. 249 
Station, Latitude. Longitude. Depth. Temperature Bottom. 
3388 7 6N: 79° 48’ W. 1168 fathoms 36.2° F. Gn. glob, Oz. 
3399 TOUTING. 81° 4’ W. Wyj4i0) 2 36° F. Gn. Oz. 
3406 0° 16’ S. 90° 21’ 30” W. ool 41.3° F. R. 
3411 0° 54’ N. 91° 9’ W. TSS ss Bose hs Y1. glob. Oz. 
3413 9° 34’ N. 92° 6 W. 1360 * 36° F. Glob. Oz. dk. Sp. 
3414 10° 14’ N. 96° 28/ W. 2232 35.8° F Gn. M. 
38418 16° 33/ N. 99° 52’ 30” W. 660 se 39° F. Br. S. bk. Sp. 
3435 26° 48’ N. 110° 45’ 20” W. 859 =“ Sisoae De Br. M. bk. Sp. 
3436 27° 34 N. 110° 53/ 40” W. S05 me See Be Br. M. bk. Sp. 
MYCTOPHOIDS. 
This group contains so many diverse forms that it has been split up into 
half a dozen families or more. Synodus, Chlorophthalmus, Benthosaurus, 
Bathypterois, Ipnops, and Myctophum, each serves as the type of a family ; 
and one or two of the other genera will no doubt on further acquaintance 
be similarly utilized. As there is no apparent advantage for the present 
report in the subdivision the group is here retained as a whole, though 
given less extent than by some of the more conservative authors. The 
Myctophoids possess a very general marine distribution. Wherever deep 
sea collections have been made individuals of various species have proved 
to be more or less abundant. Some forms are found near the surface, 
probably nocturnal, others are certainly mhabitants of regions near the 
bottom. Synodus, and species of Myctophum and of Chlorophthalmus are 
fair instances from the upper levels of the ocean, and the bathybial types 
are instanced by other species of Myctophum and of Chlorophthalmus, and 
by the genera Bathysaurus, Bathypterois, Scopelengys, and Ipnops. Bathy- 
saurus is credited with a vertical range of 1738 fathoms, going down from 
a depth of 647 fathoms to one of 2585; the records for Chlorophthalmus 
give a range of 1540 fathoms, between a depth of 85 and one of 1425 
fathoms ; from the few captures made of Scopelengys its vertical range is 
1137 fathoms, from 695 to 1852 fathoms; Ipnops has been taken at 1560 
fathoms and at 1900, giving a range of 540; and Myctophum from the 
records would appear to occur at all depths from the surface to 2620 
fathoms. 
A considerable adaptive differentiation for life in the darkness obtains 
among these fishes. Probably all of the known forms are more or less 
luminous. The possession of lanterns, luminous glands or eye-like spots, 
by many of the species suggests a natural subdivision of the group into 
