Mr. C. Spence Bate on a new Genus of Macrura. 75 
with all the group, and present a character in the presence 
of the stylocerite that distinguishes them from those 
that belong to the Trichobranchiata, and makes me much 
regret that the previously desiccated condition precludes a 
' satisfactory examination of the branchial structure. In most 
of the recent forms allied to Eryonide the inner margin 
of the first joint of the peduncle of the anntenna is 
laterally produced into a broad and thin plate which is pro- 
jected upward in the median line in consequence of its 
meeting a similar projecting plate belonging to the oppo- 
site side. In a few species it is reduced in importance 
to little more than a big tooth; but it is absent generally 
from all other genera of the Trichobranchiata. On the outer 
side there is no stylocerite such as we find conspicuous in 
all the Phyllobranchiate Macrura and exists in a modified 
form in the Dendrobranchiata. In the species now under 
consideration it is prominent, well defined, and of considerable 
tenuity, and therefore in this character approaches that of the 
Phyllobranchiata. 
The second pair of antenne have the flagellum broken; 
but from its proportions it may be assumed to have been about 
the length of the carapace or perhaps a little longer; the 
scaphocerite is leaf-like and hairy, and has the margin on the 
outer side rigid and produced to the rudiment of a tooth, while 
the inner side is fringed with fine ciliated hairs, the whole 
structure bearing a membranous character of extreme tenuity. 
The mandibles (d) are powerful organs, smooth along the 
psalisiform or cutting margin, with the molar protuberance 
short and robust, and on the outer surface there exists a 
three-jointed synaphipod or appendage, which differs from the 
typical forms of the recent Eryonide in which there are only 
two joints, but corresponds with most other families of the 
normal 'Trichobranchiata. 
The first pair of siagonopoda (e) or maxille bear a resem- 
blance to those of Wellemesia, but differ in the possession 
of a small joint on the outer side of the chief branch. 
The second pair (f/f) resemble more nearly those of the 
family Astacide and differ chiefly in not having the masti- 
gobranchial plates posteriorly produced, but rounded off 
short. 
The third pair (g) are in a more advanced condition than I 
have found in any of the typical Macrura and have the primary 
branch six-jointed and support a well-developed multiarticu- 
late basecphysis. 
The first pair of gnathopoda (4) are well developed and 
pediform, having the basis very long and furnished with a 
