Memoirs of the Indian Museum. [Vol. II, 
Subgenus Pcëcilasma, Darwin. 
Pœcilasma kœmpferi. Darwin. 
P. kæmpferi, Darwin, Mon. Cirr., Dep., p. 102, pi. ii, fig. i ; Gruvel, Zool. Travail- 
leur et Talisman, Cirrhipèdes, p. 46, pi. iv, fig. i ; Weltner , Archiv, f. Naturg., 
1897 (i), p. 243 ; Pilsbry, Bull. Bureau of Fisheries, vol. xxvi (1907), p. 183, 
and Bull. U. S. Nat. Mus., No. 60, p. 84, pi. vi, figs, i — 5, 13 and 14; 
Annandale , Illustr. Zool. “ Investigator Crust. Ent., pi. iii, fig. i. 
P. aurantium, Darwin, op. cit., p. 105, pi. ii, fig. 2 ; Hoek, Siboga-Exped., Mon. 
xxxi«, Cirr. Ped., p. 7. 
P. dubium, Hoek, op. cit., p. 6, pi. i, figs. 2 — 4, pi. x, figs. la — d. 
Capitulum more or less narrowly ovate ; the carinal margin much more strongly 
arched than the occludent margin; apex pointed, valves five, stout, closely approxi- 
mate. Ter gum triangular; the carinal angle slightly truncated, the others sharp; 
the scutal margin straight. Carina arched, ending in a very small and imperfect disk 
at the base, tapering above, almost of the same width throughout or widest at the 
base ; above extending a short distance between the terga. Scutum entire, much 
longer than broad, with a more or less distinct ridge running down it near the 
occludent margin ; internal umbonal teeth feebly developed or strong. 
Peduncle slender, variable in length, ringed, naked. 
Cirri, etc. — Rami of first cirrus nearly equal ; second cirrus widely separated 
from first. Anal appendages about ^ length of the pedicel of the sixth cirrus, with 
bristles at the tip and down the whole of the posterior margin. Penis long, stout, 
hairy. 
Mouth parts. — variable. Maxilla has “two large upper spines, the 
edge deeply notched below them, sparsely spiny in the notch. It then protrudes and 
is rather closely set with spines ” (Pilsbry). 
Several forms have been described which seem to be subspecies or local races of 
P. kæmpferi. The Indian specimens I have examined do not quite agree with any 
figure I have seen. Unfortunately I have only been able to examine six individuals 
from any Oriental locality. All of them were taken in the Gulf of Manaar on the 
shell of a “ spinose crab” {Echinoplax pungens) at a depth of nearly 500 fathoms. 
They come nearest to the form recently described by Hoek as P. dubium, but their 
Carina is intermediate between that of this form and that of the specimen figured by 
Darwin. Pilsbry’s figure, however, of the carina of a Japanese specimen does not 
altogether agree with Darwin’s, although the latter’s .specimen was also from Japan. 
In my specimens the occludent margin projects less beyond the vertical ridge on the 
scutum than it does in Hoek’s figure, but a little more than it does in Darwin’s. On 
the whole, I think that it is possible to distinguish five local races of the species, and 
that they may be distinguished as follows : — 
Race I (typical form). — A single vertical ridge on the scutum. Occludent margin 
of the scutum projecting very little beyond the vertical ridge, evenly curved ; 
