1909.] 
N. Annandale : The Indian Cirripedia Pedunculata. 
113 
of the sixth cirri, slender, slightly spatulate, rounded at the tip, which bears a pencil 
of stout hairs, some of which are considerably longer than the appendage itself : the 
upper third of the posterior edge bearing similar hairs. Penh slender, abruptly 
pointed at the tip, moderately long, clothed with closely set rings of minute spines 
and bearing a few scattered hairs. 
Mouth parts. — Labrum broad, bearing a row of short, rather stout teeth. 
Palpi short, slender, bearing a pencil of long hairs at the tip. Older maxillce broadly 
oval, densely fringed. Maxillce with a broad, rather shallow, pointed incisure near the 
outer edge, which is armed with a long, slender spine ; between this and the incisure 
two or three more slender spines of varying length ; a long slender spine immediately 
on the other side of the incisure followed by several others (usually six) of varying 
lengths ; the inner edge of the appendage irregularly serrated and bearing a fringe 
of fine hairs. Mandibles bearing five teeth, the outermost of which is by far the 
largest and is separated widely from the rest ; the fourth tooth short and often blunt, 
the fifth slender and rather long ; the four inner teeth and the part of the appendage 
adjacent to them clothed with minute spines ; the inner edge of the appendage bear- 
ing a fringe of fine hairs. 
I have examined some twenty specimens of this species from the entrance to the 
gill-chambers of two deep-sea crabs. 
Specimens. 
Gill-chambers of Geryon affinis. Stat. 248 (hat. 8° 37' N., Long. 75° 37' 30" 
E., Laccadive Sea), between 224 and 284 fathoms. (S.S. Investigator.”) 
^10“ Gill-chambers of Geryon quinquedens. “ Martha’s Vineyard ” (off coast of 
New Jersey, U. S. A.), 328 fathoms. (Smithsonian Institution.) 
Remarks — 
This species is variable as regards the exact form of its valves, the colour of the 
membrane, the relative lengths of the capitulum and peduncle, and the proportions of 
the latter. The lower branch of the scutum is sometimes broadly triangular, occa- 
sionally almost linear, the outline of the tergum differs greatly in different individuals 
and the carina sometimes ends practically at its lowest point and is sometimes pro- 
duced into horizontal branches, which may underly the extremity of the basal 
branches of the scutum. The specimens from Geryon quinquedens have a deep orange 
colour and are very opaque, while those from G. affinis are colourless and much more 
translucent. In all, the valves are yellowish and apparently contain a large proportion 
of chitin. Speaking generally, I may say that both the peduncle and the capitulum 
are more slender in older than in young individuals, in which the former is often .some- 
what narrowly oval, while in older (or at any rate larger) examples it is broadly trian- 
gular. Even the narrow, oval individuals, however, often bear ova. There is one 
character shown by some individuals among those from Geryon quinquedens {viz . , 
the transverse fission of the carina) which seems to justify them being considered a 
distinct variety, for which the name var. fissicarina is proposed. 
