SP0NG1I;LA-FLIKS PARFIN AND GURNEY 439 



ring five long setae, and the smaller, three. On the ninth, the 

 fe'?ral tubercles are more complex, with three to five long setae. 

 Vitrally, on the eighth and ninth segments, is a transverse row of 

 f(r setae, the median pair closer together on the eighth segment 

 tin on the ninth (particularly close in vicaria) ; also on the ninth, 

 3iall, narrow tubercles on each side ventrally bear long setae, usually 

 ttD in mcaria and three in californica and areolaris (fig. 4). On 

 tl' tenth segment, small hairs are visible and a pair of eversible 

 alominal appendages (rarely used, according to Withycombe, 1925, 

 p332) are also present; the tenth segment is longest in vicaria. 



Die dorsal setal sclerites or plates are now clearly defined and 

 aume shapes of specific importance. Those of vicaria, areolaris, 

 al californica are compared in figure 5. It is seen that those of 

 mria and californica closely approach each other in general, with 

 tJ)se of the first three abdominal segments appearing more pedun- 

 cate in vicaria. Around the bases of the setae are found minute 

 Sialike projections in areolaris. 



The folded, ventral, tracheal gills on the first seven abdominal 

 S'iments of vicaria (fig. 3,i) were examined and described by Anthony 

 ()02, pp. 618-619, fig. 5). Although Westwood (1842, pi. 8, fig. 210) 

 fiured the gills with five joints, Anthony found only three segments 

 o' the second to seventh pairs, but two on the first pah-, which seemed 

 t lose the articulation between the first and second segments. As 

 pinted out by Anthony, the first pair has a basal hooklike projection, 

 viich gradually decreases in prominence, disappearing almost entirely 

 the gills of the posterior segments. On each pair of gills except 

 t3 first, the first segment is shallowly notched at its articulation 

 pint with the second, with the basal end considerably longer and 

 pre curved than the distal. The point of attachment of the straight, 

 sorter, second segment is at the notch. The gills are transparent, 

 snder, acute distally and directed posteriorly while at rest. In 

 h, they often extend beyond the abdomen almost as far as the 

 l;ig setae. Browm (1952, p. 145) noted that the gills are intermit- 

 titly vibrated most of the time, so that the ventral surface of the 

 Idy appears blurred. 



The gills of Climacia appear to be similar in structure to those of 

 tsyra. On the specimens examined, they appeared sometimes with 

 t;e first segments broad and the terminal ones either partially absorbed 

 c missing. The spiracles can be seen anterior to each of the lateral 

 Ibercles on the first eight segments. 



The color of the larva appears to vary from brownish to greenish, 

 (pending to a certain extent upon the sponge fed on. A faint indica- 

 i)n of brownish black pigmentation along the middorsal line was 

 'sible on some of the specimens in the form of paused anterior spots. 



