21 



all the species, so far at least as our present knowledge goes, have a limited geographical 

 distribution. We need not forget, however, that our knowledge is rather imperfect as yet. In 

 one of the last papers published on Cirripedia (that in which Annandale describes the stalked 

 Cirripeds of the Colombo Museum) we find in this regard as new facts that D. eqicina Lanchester 

 from the east coast of the Malay Peninsula is common on the east coast of British India 

 and that D. pelliuida Darwin is an Oriental species which probably has a fairly extensive 

 distribution. The latter, which has only been taken on sea-snakes, has not been collected during 

 the cruise of the "Siboea". 



t> 



I. Dichelaspis Nierstraszi n. sp. PL 11, fig. i — 7. 



Capitulum much compressed, with the apex produced. Scuta with the basal segment 

 about as wide as the occludent segment, its carinal margin being very much hollowed out; 

 terga with three unequal marginal projections the longest of which is nearly as wide as the 

 occludent segfment of the scuta. Carina terminating in a disc. 



General appearance (PI. II, fig. i and 2). Capitulum compressed, flat, slightly convex 

 in the middle, with the apex produced. The valves are covered by a membrane which is thick 

 and hairy especially in old specimens. In very young specimens the membrane also bears 

 chitinous hairs. The carina is separated by a wide space from the scuta. Peduncle cylindrical, 

 shorter than the capitulum. 



The valves cover a large part of the surface in very small specimens (PI. II, fig. 20). 

 In these the shape of the valves is also different. 



Scutum (fig. 4«). It is formed of two slightly divergent and about equally broad parts, 

 hanging together by means of a very narrow bridge. The occludent segment one fourth longer 

 than the part representing the basal segment; both .segments with the upper part the broader. 



In some old specimens from the Tual anchorage, Kei Islands, the occludent segment 

 of the scutum is considerably wider than the basal segment. 



In very young specimens (fig. 2a) both segments of the scutum are relatively broader; 

 this is especially the case with the basal segment, the shape of which is nearly triangular, with 

 the carinal margin hollowed out. Fig. 3« represents the scutum of a middle-sized specimen, 

 remarkable for having the upper part of the occludent segment rather narrow. 



Tergum (fig. 4^). It has the lower part of about the same width as the occludent 

 segment of the scutum ; a narrow occludent segment forms a second projection which is separated 

 by a deep notch from the carinal segment; the apex of the occludent segment of the scutum 

 extends in the direction of this notch. A third and very short prominence is placed high up 

 on the carinal margin just above the apex of the carina. 



In very young specimens (fig. 2a) the three prominences of the tergum are not so well 

 developed as yet; the middle one, the longest of the three, is the only one distinct. In middle- 

 sized specimens (fig. 3^5) the tergum has about the shape as the full-grown individuals. 



Carina (fig. 5 and ^a). Much bowed, narrow, deeply concave within, extending up 

 between the terga for '\^^^ of their length, with a very characteristic curvature directed inwards 

 just above the basal part. Downwards it terminates in a rectangularly inflected, deeply imbedded 



