NEMATOCARCINUS ENSIFER. 157 
Station 3415. 1360 fathoms. 1 specimen. 
oan Log 76 5 . 
eeo es OOO! 6 SOs 
SSnotad 676 < 36 se 
“8425. 680) 4] es 
es430. 852° 6 ee 
Emoto: GOR” i 3 eS 
ce 3450. 859) 6 14 eS 
ey 0400.) - 90am Wi 17 = 
This species has been previously known from off the eastern coast of the 
United States (lat. 51° 41’ N. to 41° 43’ N., 588 to 2033 fathoms) through 
the explorations of the “Blake” and the “ Albatross.” The Pacific speci- 
mens, like those from the Atlantic side of the continent, vary considerably 
in the length and trend of the rostrum, which may be either straight and 
horizontal, or curved considerably upward. In some specimens, moreover, the 
rostrum is armed on the lower margin with from one to three small teeth 
which are wanting in the typical form, and this variation is almost invariably 
accompanied by a difference in the abdominal segments. In the typical 
form, without inferior rostral teeth, the dorsum of the third abdominal seg- 
ment is prolonged into an acute tooth over the fourth segment, while the 
succeeding segments are laterally compressed near the dorsum so strongly 
as to present an almost carinated appearance. In the specimens with in- 
ferior rostral teeth the third abdominal segment is prolonged backward over 
the following segment in a less degree, and the prolongation is rounded off 
behind instead of ending in a sharp point. The dorsum of the succeeding 
abdominal segments, too, is rounder than in the typical form. The typical 
form is the more southerly in its distribution, ranging (as far as the collec- 
tion at hand determines) from 0° 36’ S. to 7° 5’ 80” N. (Stations 3363-3413), 
while the other form is found between 16° 33’ N. and 27° 54’ N. (Stations 
3418-3436). In rare cases, as in the specimens from Station 3415 (an inter- 
mediate locality, be it observed), we find the rostrum of the typical form 
combined with the abdomen of the more northern race. 
