REMABKABLT BEANCUED SYLLIS. 



723 



the sponge. It closely agrees with the description of the fore- 

 going speciincu, except iu the larger garuet-tiatcd eyes, and the 

 presence of beautiful tufts of long simple bristles ia each foot. 

 Its length is about 9 millims., and its breadth, including the latter, 

 rather more than 2 millims. There are twenty-nine segments, 

 but the condition of the tail is open to doubt. Dorsally each 

 segment has a slender and distinctly jointed cirrus. Beneath the 

 foregoing, is a dense tufc of long, translucent, simple bristles, with 

 broad flattened tips after the fashion of the straight Boman 

 sw ords, but marked at the tip by two peculiar longitudinal pro- 

 cesses, and sometimes the end assumes a fimbriated appearance. 

 The setigerous region beneath is short and conical, having 

 superiorly the spine and inferiorly the bristles, which differ from 

 those of the parent- stock in showing a more evident differentia- 

 tion at the junction of the terminal process. Yentrally is a 

 tongue-shaped cirrus, which nearly reaches the tip of the seti- 

 gerous region. The entire body is filled with ova, which like- 

 wise occupy the feet almost to their tips, the first segment and 

 the extremity of the tail (which is apparently in process of re- 

 generation) alone being devoid of them. Some of the feet, indeed, 

 assume a bulk four or five times larger than the others, from 

 distention with ova. The latter apparently have embryos in- 

 ternally. 



Amongst the tangled masses in the channels of the sponge is 

 a fragment of the posterior end of a form which differs from 

 either of the foregoing. The feet, which are w^ell marked and 

 long, have dorsally a slightly convex margin ; ventralJ; the out- 

 line is also somewhat convex at the base, but curvus upward 

 toward the tip. A short cirrus of four or five segments ex- 

 tends from the extremity of the dorsal margin, while beneath it 

 is a dense tuft of long, straight, sword-shaped translucent bristles, 

 similar to those described in the female bud. A flat papilla, 

 about the middle of the bristle-bundle, shows that part of the 

 foot to which the tip of the slender supporting spine proceeds. 

 This slender spine diverges upward from the side of the stronger 

 inferior one, the arrangement of the parts indicating that the 

 foregoing tuft of simple bristles is of less morphological value 

 than the others. A somewhat lanceolate process occurs at the 

 ventral margin of the foot, and apparentlj^ corresponds to the 

 setigerous division. It is supported by the stronger spine, and 

 bears two or three bristles with simple terminal processes, similar 



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