92 Memoirs of the Indian Museum. [Voi,. II, 



Pœcilasma fissum, Darwin. 



P. fissa, Darwin, Mon. Cirr., lycp., p. 109, pi. ii, fig. 4 (1851). 



P. fissum, Hoek, Sihoga-Exped., Mon. xxxia, Cirr. Ped., p. 8, pi. x, figs. 2 — 5 

 (1907); Annandale, Illustr. Zool. " Investigator ^ Crust. Ent., pi. iii, fig. 8. 



P. amygdalum, Aurivillius, ''Stud. ii. Cirr.," K. Svensk. Vet.-Ak. Handl., xxvi, 

 No. 7, p. 10 (1894). 



? P. lenticula, id., ibid., p. 12. 



Capitulum ovoid, narrowly rounded above, the carinal margin somewhat more 

 boldly and more regularly arched than the occludent; valves not in close contact with 

 one another. Scutum divided, the two segments often diverging to some slight extent 

 above, the occludent segment narrow, especially so in its lower half, its upper extremity 

 more or less pointed ; carinal segment broad, slightly inflated, its anterior border 

 almost straight, its tergal and carinal borders forming an almost uninterrupted curve. 

 Carina reaching the basal angle of the tergum above, forming a very small transverse 

 disk at the base, which is concealed beneath the cuticle ; no definite dorsal or lateral 

 ridges. Tergum subtriangular, the apex being more or less rounded; the occludent, 

 and sometimes the carinal angle also rounded. 



Peduncle short, irregularly annulated, often ornamented with small spines or 

 plates. 



Cirri, etc. — " Cirri of the first pair have unequal rami of respectively 



6 and 9 segments. These segments are broad, short, quadrangular, bearing at the 

 extremity a transverse row of numerous spines, which are longer than the segments 



themselves." " Cirri of the second to sixth pair have rather short pedicels and 



also short rami of 11 and 12 segments what is especially characteristic 



for this species is, that the pairs of spines which as a rule in other Cirripeds are 

 seen at the anterior faces of the segments of the cirri are totally wanting" (Hoek). 



Mouth parts. — " Labrum with a row of about 24 small teeth, standing close to- 

 gether; at each side the five or six outer ones are sharply pointed, the dozen in the 

 middle being rather blunt. Palpi small, conical, with about five longer hairs at the 

 tip and a few smaller ones along its inner side." 



" According to Darwin the fourth tooth of the mandible is pectinated. I found 

 a small tooth on the inner edges of the second and third teeth, one on the outer edge 

 of the fourth tooth and also one on the edge of the inferior angle." 



"The maxillcB were unknown to Darwin. The upper part is furnished 



with three spines : two claw-like and the third rather straight and more delicate ; 

 .... Under the upper part there is a deep notch, on the inferior margin of which 

 two minute hairs are planted. The inferior part of the edge of the maxilla is much 

 produced and bears about ten unequally stout spines. Of these the one placed 

 about the middle is by far the strongest " (Hoek). 



The species appears to be rare though widely distributed. Darwin examined a 

 single specimen (dried) from the Philippines, Hoek found a large number on a " Pali- 

 nurus ' ' taken at Ternate, and others have been recorded by Weltner. The only 



