108 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
7. Rocinela laticauda, n. sp. 
Plate III. Fig. 2-2e. 
Three specimens of very different size, one a large and in all probability adult 
male ; no female with marsupium. 
Head. The eyes of medium size, the shortest distance between them about 
as long as the last joint of the peduncle of the antenne ; the distance in the 
smallest specimen is comparatively a little shorter than in the largest one. 
Antenmule. They surpass a little the middle of the last joint of the peduncle 
of the antenne (Fig. 2a); the peduncle reaching a little beyond the extero- 
anterior angle of the third joint of the peduncle of the antenne ; the flagellum 
in the small specimen with five, in the large specimens with six joints. 
Antenne. They reach a little beyond the middle of the third thoracic seg- 
ment ; che flagellum in the small specimen with fifteen, in the two other 
‘specimens with sixteen joints. 
Thorax. The epimera (Fig. 25) of second and third thoracic segments 
posteriorly rounded and not produced, those of the fourth segment somewhat 
produced with rounded apex, those of the three posterior segments considerably 
produced and almost acute. i 
Thoracic Legs. The three anterior pairs (Fig. 2 c) tolerably stout : the fourth 
joint with about four acute spines, some of them rather long ; the sixth joint 
quite as broad as the fourth, its large and broad expansion on the inner side 
with six spines. The four posterior pairs (Fig. 2d) with numerous slender 
spines. 
Abdomen (Fig. 2¢). The first segment is entirely concealed under the last 
thoracic one, The abdomen increases very conspicuously in breadth from the 
second to the fourth segment. The last segment is large and broad, posteriorly 
very broadly rounded ; the dorsal surface is keeled anteriorly in the middle, 
and from the keel towards the lateral margin it is rather deeply, or, in the 
two smaller specimens, deeply and broadly depressed, the depression not 
reaching the lateral margin; the posterior margin with a number of very 
small spines. 
Uropods (Fig. 2e). They surpass a little the last abdominal segment. The 
outer ramus reaches very little beyond the inner one, is considerably, but not 
1} times, broader than this, and is furnished with a number of spines on a 
larger part of its exterior margin. Thainner ramus with spines on the terminal. 
margin, and on the larger part of the outer margin. 
1 Schiödte and Meinert write (Nat. Tidsskr., 3 R., Bd. XII. p. 383) on the species 
of the genus Rocinela: “Bene recordari debet, discrimen, quod individua speciei 
unius ejusdemque quoad figuram frontis atque sculpturam partis prioris trunci 
preebent, non sexum, sed »tatem diversam notare,” This observation is a very 
valuable one, as the differences in the front sometimes lead to great confusion. 
The frontal plate seems to be very small in all species; the thoracic epimera show 
much smaller differences in the various species than in the species of ga. 
