Pemphix, Glyphea, and Areosternus. 311 
of the cephalothorax of Glyphea is semilunar; and M. De 
Man describes this part of the cephalothorax of Arcosternus 
as “the curved posterior margin of the upper surface of the 
cephalothorax.” It appears therefore that the general form 
of the cephalothorax of Glyphea does not materially differ 
from that of Arwosternus. 
A transverse furrow, the cervical groove, a little behind the 
middle of the cephalothorax, divides the carapace of all the 
Glyphee into two principal parts. This groove, which is rather 
deep on the two sides of the back, is directed forwards and 
downwards. See the description of this groove in Glyphea 
Lundgrent, Schliter (Verhandl. Rheinl. und Westfalens, 1874, 
p- 48). It is remarkable that M. De Man speaks nearly in 
the same terms of the cervical groove of Arcosternus :—“ The 
cervical groove occurs a little behind the middle; its lateral 
parts are directed downwards and forwards towards the ante- - 
rior part of the sternum.” There is therefore no essential 
difference in this character. 
The abdomen of several species of Glypheew is perfectly 
smooth ; there are only some of them in which that part of 
the body is adorned with a few scattered tubercles. ‘That of 
Areosternus is also smooth—that is 10 say, without tubercles 
or spines; only it is ornamented with a multitude of small 
tufts of hairs, except on the superior or dorsal surface. The 
lateral plates of the segments of the abdomen are also of the 
same form in both genera. 
In both genera the ocular peduncles are cylindrical and 
lodged in sinuses of the anterior margin of the cephalothorax. 
M. De Man calls these sinuses in Arcosternus ‘deep trian- 
gular notches, into which the eyes project,’ which may 
almost be said of the genus Glyphea. | 
The jaw-feet of the Glyphee consist of four joints, like 
those of Arwosternus. 
The ner antenne of the Glyphee consist of a peduncle 
composed of three joints and of two multiarticulate ter- 
minal filaments. ‘The inner antenne of Arwosternus, ac- 
cording to M. De Man, are like those of the Palinurt; that 
is to say, the first joint is the longest and extends as far as the 
carpocerite of the outer antenne; the second and third joints 
are of equal length, and together as long as the basal joint; 
and the terminal filaments are very short. It would there- 
fore seem that these organs in the two genera only differ in 
the relative length of the filaments. 
The outer antenne of the two genera are exactly alike 
as regards the joints of their peduncle and the multiar- 
ticulate terminal filaments, which are a little shorter than 
