ISOPODS COLLECTED AT THE HAWAIIAN ISLANDS 
823 
EPICARIDEA or BOPYROIDEA. 
Family DAJ1D£. 
ZONOPHRYXTJS Richardson, gen. nov. 
Type, Zonophryxus retrodens Richardson, sp. nov. 
Body of female provided on the ventral side with a border which surrounds it on all sides, and 
which is wider in the anterior or cephalic region. The posterior portion of this marginal border is 
provided with nine small triangular processes, four on either side of the median one, and undoubtedly 
indicates five coalesced abdominal segments. Five pairs of legs are present on the anterior half of the 
ventral side. Five pairs of incubatory lamellae on either side of the ventral surface meet in the median 
line, the fifth pair being narrow and elongate and concealing the second and third pairs, which are 
very small, and a part of the fourth pair. Dorsal surface convex, with only faint traces of segmentation, 
the boundaries of the three divisions of the body not being indicated. Small incisions at the side of 
Fig. 4 . — Zonophyryxus retrodens. (a) Dorsal view, x 6.6; (6) Ventral view, x 6.6; (c) Maxilliped, x 9.33; (d) First lamella 
of marsupium (right side), x 9.33: 
the anterior half of the body on the marginal border probably indicate the place of separation of the 
head from the thorax, the first thoracic segment from the second, and the second from the third. 
Male with the first thoracic segment fused with the head. All 7 pairs of legs present. Segments 
of abdomen consolidated into one. 
This genus differs from all the other Dajidx in having a marginal border surrounding the body 
and in having nine triangular processes on the posterior margin of this border, representing 5 coalesced 
abdominal segments. 
It differs from Dajus Kroyer in having the segments of the abdomen fused in the female; in having 
but slight traces of segmentation in the thoracic region, and in both male and female lacking uropoda. 
It differs from Branchiophryxus Caullery in having 5 pairs of legs and 5 pairs' of incubatory lamellae, 
only 4 pairs of legs and of incubatory lamellae being true of Branchiophryxus, and in having a single 
pair of pleopoda, which are altogether wanting in that genus. It differs from Notophryxus Sars in the 
form of the abdomen and head, and in having 5 pairs of incubatory lamellae instead of a single pair. 
It differs from Aspidophryxus Sars in the form of the head and abdomen of the female, and in having 
no trace of segmentation or appendages to the abdomen of the male. 
