MUSEUM OF COMPARATIVE ZOOLOGY. 95 
Fig. 1c). The first segment is quite concealed above, and the second more 
or less concealed also in the ordinary position of the segments. In the ventral 
portions of the first three pleonal segments the posterior angles are rounded 
instead of being acute, as in both the C. polita and C. concharwm ; laterally the 
second, third, and fourth segments are ciliated, as in both those species. The 
telson (Pl. II. Fig. 3) is much like that of C. polita (Pl. II. Fig. 2). The 
uropods have the basal segment produced internally; the outer ramus is about 
half as wide as the inner, which has a distinct notch near the distal end of the 
outer border and is obliquely truncate, or, in the larger specimens, emarginate 
at the end; both rami, like the end of the telson, are strongly ciliated, but 
sparingly spinulose. The telson is distinguished from that of C. concharum 
(Pl. II. Fig. 4) by the emargination at the tip in that species. The stylet on 
the second pair of pleopods in the male (Pl. I. Fig. 3) is simple, ensiform, and 
tapers to a blunt point ; it surpasses the lamella to which it is attached. 
The four large females of this species obtained by the Blake Expedition 
measure in length 21-23 mm. and in breadth 6-6.5 mm. Specimens obtained 
by the U. 8. Fish Commission are many of them smaller, but vary from 15 to 
27 mm. in length. 
The specimens were obtained at Station 336, Lat. 38° 21’ 50” N., Long. 
73° 32’ W., from a depth of 197 fathoms. Others have also been obtained by 
the U.S. Fish Commission at the following stations: — 
Station, Fathoms. N. Lat. W. Long. Specimens. 
871 115 40° 2) 24" 70° 23’ 40” 4 
949 100 40° 3! 70° 31’ il 
1094 301 39° 57’ 69° 47’ i 
1095 321 39° 55’ 28” 69° 47’ 2 
AHGID A. 
Aga psora (Linnt) Kroyer. 
One specimen from 306 fathoms at Station 303 in Lat. 41° 34’ 30” N., 
Long. 65° 54’ 30” W. 
?1 Aga Webbii (Guérim) Scuiépre & Mervert. 
Pterelas Webbii Gutrin, Mag. Zool., Classe VIL, Pl. XX. 1836. 
ga Webbit ScuioptTe & Murnert, Naturhist. Tidssk., R. IIL, B. XII, p. 347. 
Pl. X. (Cym. IV.) Figs. 1-4. 1879. 
A single immature specimen of this, or a closely allied species, was taken 
at Station 307, Lat. 31°57’ N., Long. 78° 18’ 35” W., from a depth of 333 
fathoms. It measures 10.5 mm. in length, 5.5 mm. in breadth, and has not 
yet developed the seventh pair of legs, but the propodi of the second and third 
pair of legs are armed with the characteristic cultriform spine, and I have 
referred it to this species, though not with certainty. 
