HYMENODORA GLACIALIS. 169 
next obtained by the Norwegian North Atlantic Expedition, 1876-1878, at 
several stations between Norway and Greenland, lat. 63°-80° N. All the 
specimens were brought up from great depths, 452-1862 fathoms. It has 
been taken more lately by the “ Knight Errant” in Firde Channel, and by 
the “ Albatross” off the east coast of the United States, lat. 87° 12’ 20” N., 
and 38° 19’ 26” N., in 2369 and 2949 fathoms. The rudimentary condition 
of the eyes would seem to indicate that the first specimen obtained was 
brought to the surface by some accidental cause. It should be noted that 
the identity of Buchholz’s specimen with those more lately obtained rests 
upon the assumption of error in Buchholz’s figure, in which the abdominal 
pleure present a very different outline from that exhibited by the examples 
subsequently secured. 
The uniformity of the conditions affecting animal life in the abysses of 
the ocean the world over could not be exemplified more strikingly than by 
the discovery of this animal in the tropical Pacific to within 1° 7’ of the 
equator. 
The number of teeth on the median keel of the carapace varies in differ- 
ent specimens from one to four. The acumen of the rostrum also varies in 
length, even in specimens from the same haul of the dredge. 
I have examined the structure of the second maxilliped in four speci- 
mens,—two from Station 3383, and two (males) from Station 3433. In 
the first two there is no trace of a podobranchia. In one of the specimens 
from Station 3433 there is likewise no vestige of a gill, while in the 
other, although it does not differ in any other regard, there is a distinct, 
though small, podobranchia, composed of three plates, attached to the base 
of the epipod. I therefore incline to the opinion that Professor Smith’s 
H. gracilis,* characterized by the presence of a podobranchia on the second 
maxilliped, was injudiciously separated from H. glacialis. It is to be observed 
that the gill varies much in its degree of development in different speci- 
mens of H. gracilis. 
The telson in the Pacific specimens is seen in its integrity in but two 
cases. In these the number of terminal spines is six and eight. 
* Ann. Rep. U.S. Fish Comm. for 1885, p. 680, Plate XII. Fig. 6, 1886. 
