içog.J N. Annandale : The Indian Cirripedia Pedunculata. 121 
figure but exist as slightly raised linear ridges marking the limits of the original five 
valves. I would therefore regard the form at most as a variety of D. cor. 
Dichelaspis sinuata, Aurivillius. 
D. sinuata^ Aurivillius , op. cit., p. 17, figs. 2 — 5. 
D. trigona, id., ibid., p. 19, pi. ii, fig. 8. 
D. vaillantii, Gruvcl, op. cit., p. 279, pi. xiv, figs. 5 — -13; Annandalc, Illustr. Zool. 
“ Investigator Crust. Ent., pi. iv, fig. 6. 
vSmall, more or less transparent ; the scuta and carina linear ; a pair of calcified 
terga present ; chitinous points absent on the external surface, or very minute. 
Capitulum somewhat variable in shape, more or less globose, usually having a 
distinct lobe on the upper extremit}" of the occludent margin ; both edges arched. 
Tergum small, saddle-shaped or vertically elongate, occasionally almost square, fully 
calcified. Scutum imperfectly calcified as a rule, consisting of two more or less elon- 
gated, slender branches, which meet together at a point considerably removed from 
the base of the capitulum (in well-preserved specimens), the basal branch being nearly 
transverse and the occludent branch sloping towards it in such a way that the result, 
ant angle would be less than a right angle if it were not rounded off ; the two branches 
equal or nearly equal in length, pointed at the tip. Carina sometimes reduced to a 
mere rudiment of a narrowly triangular outline and only occupying a very small part 
of the dorsal border of the capitulum, more commonly longer and produced at the 
base into a pair of branches, which are long and slender in some individuals and 
barely represented even by minute rudiments in others. 
Peduncee generali}’ longer than the capitulum, but sometimes much shorter. 
Cirri, etc. — Cirri short, slender and by no means strongly curved. The first pair 
not so widely separated from the second as in some species, very short, subequal, 
without stout spines, but profusely covered with delicate hairs. Anal append- 
ages slender, reaching beyond the apex of the pedicel of the sixth cirri, compressed, 
rounded at the tip, which bears a double row of some five to seven moderately long 
hairs ; these extend a short distance down the posterior margin. Penis slender, not 
very long, the tip very fine, ending in a bunch of fine hairs, not retro verted. 
Mouth part.s. — Lahrum more or less bullate, with about twelve minute, round, 
blunt teeth on the upper surface. Palp conical, bluntly pointed, long, covered with 
fine hairs and bearing six or seven irregularly placed pairs of stout bristles on and 
near the tip. Outer maxilla broad, almost heart-shaped, with a fringe of fairly stout 
hairs on the dorsal surface. Maxilla without or with a very faint incisure ; the 
bristles not so stout as in D. cor and showing greater differences in size. Mandible 
with five teeth in addition to the inner angle, but with the inner angle either blunt or 
divided up more or less regularly into two smaller teeth ; the fifth tooth small and 
blunt ; none of the teeth very long ; the first by no means widely separated from the 
others. 
The capitulum of the largest specimens measures less than 3 mm. in length. 
