﻿252 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 102 



anal segment not demarcated by discernible transverse grooving either 

 dorsally or ventrally in specimens examined, but with a pair of raised 

 longitudinal dorsal ridges as in female, particularly noticeable in 

 stained specimens. Both ventral and dorsal surfaces covered vs^ith 

 scattered spinules. Caudal rami slightly less than one-third longer 

 than the abdomen, flattened laterally as in female, with proximal 

 dorsal ridges, inside margins with long hairs, outside with spinules. 



Second antenna (pi. 14, fig. 10) reduced in size but very stout; basal 

 segment unarmed, strongly united to ventral face of carapace (this 

 segment is apparently omitted in C. B. Wilson's illustration, 1935a) ; 

 second segment stout and well rounded, projecting upward, armed 

 below with a broad but rather short spine, and a comparatively large, 

 2-layered, fringed lamina placed distad to the spine. Third seg- 

 ment with a stalked spine, segmented near its tip, and a stalked seta 

 at the base of the claw. Claw short, but very strongly curved, with 

 a rounded projection at its inner base. (The illustration of this ap- 

 pendage, pi. 14, fig. 10, is a flattened, semidiagrammatic view, turned 

 so as to include detail of all the armature.) 



Lateral prehensile hooks scarcely larger than those of female, but 

 much more strongly curved, papillary setae unbranched. Anterior 

 accessory process like that of female, but comparatively smaller. In- 

 ner piece of first maxilla (pi. 12, fig. 12) bifurcate at tip, inner branch 

 the longer; basal portion of the outer piece broad, extended distally 

 into a long spine as in female ; setae of papilla unequal (pi. 12, fig. 15) . 

 Maxilla 2 as in female. Maxilliped (pi. 14, fig. 11) about twice the 

 length of the second antenna, Avith a stout claw bearing a stalked seta ; 

 basal segment with a short, rounded process whose tip is more or 

 less demarcated by a roughened area. Posterior accessory process 

 behind maxilliped a stout triangular spine like that of female. Chitin 

 rod between legs 1 and 2 also resembling that of female. 



Legs 1-3 with setal formula and laminae like female. Basal seg- 

 ment of leg 4 (pi. 12, fig. 19) armed marginally with spinules; more 

 spinules scattered over the upper part of the dorsal surface, and the 

 lower part with a patch of long, stiff hairs running crosswise. The 

 large spines of segments 2-4 more slender and comparatively longer 

 than those of female ; all having toothed margins, that of the longest 

 terminal spine with the proximal teeth enlarged on the inner margin. 

 Length of the shorter inner spine not known, as it is unfortunately 

 broken off in all the specimens, including the allotype. 



Development Stages : Two female chalimi, not mentioned by C. B. 

 Wilson in his report, are present in the Galapagos collection. In the 

 following descriptions, they are referred to as Stages a and h. 



Stage a (pi. 12, fig. 2) : Total length, 4.2 mm. All the first three 

 thoracic segments incorporated in the carapace, which is as wide as 

 long. Frontal plates indistinct. Free thoracic segment only slightly 



