230 Mr. A. O. Walker on the Isopoda and Amphipoda 
fourth are about the same length and much longer than the 
fifth; the first joints of all are long and narrow, with parallel 
mar gins, those of the third and our th are as long as the 
next three joimts together and about equal to the fifth joint; 
all the dactyh rather long. 
The peduncles of the third uropods are nearly four times 
as long as the rami, which are about equal to the telson. 
The nearest allies of this species are H. schizogeneios, 
Stebbing, and H. crucipes, Bovallius; it differs from both in 
having only two of the mesosome segments coalesced and in 
the greater length of the perzopoda, the form of their first 
joint, &e. It is possible that Lestrigonus rubescens, Dana, 
may be the male of this species. 
Two females with ova. Length 4°5 millim. 
Net 6a, 150 fath.; 6, 510 fath. 
Parathemisto oblivia (Kroyer). 
Several young, the largest being 7 millim. long. 
Nets 1 a, 16, 1c, surface to 50 fath. 
This is a common species in the young state on the west 
coast of Ireland. 
Phronima sedentaria, Forskal. 
One female. Length 20 millim. Net 5/, 1710 fath. 
Phronima atlantica, Guérin-Ménéville. 
One female. Length 12 millim. Net 4 e, 1170 fath. 
One young. 2 7 oe) oy) 2f; 620 oy) 
5) 29 29 2 d, O74 2) 
The last specimen agrees very nearly with P, tenella, 
Stebbing. All the above, including P. tenella, are referred 
by Chun to P. sedentaria. This author (Bibliotheca Zool. 
vol. vil. 1894-6, Heft xix. p.110) has the following remarks :— 
“The young Phronimas leave the protecting ‘house’ at the 
beginning of summer and sink to great depths. They grow 
to a length of 10 mm., when the females, after obtaining a 
‘house’ of Pyrosoma, Salpa, or Siphonophora, rise to the 
surface in the course of the winter. When sexually mature 
—in spring in the Mediterranean, but in January at the 
Canary Islands—the males also rise to the surface and visit 
the females in their ‘ houses,’ reaching the length of 12 mm. 
and rapidly acquiring their perfect antennz. They never 
attain the size of the females, which sometimes measure 
40 mm.’ 
