174 



THE SPONGES OF THE WEST-CENTRAL PACIFIC 



Text Figure No. 114. Pararhaphoxya tenuiramosa. A: Sketch of the entire sponge, 



X i; this is NOT a camera lucida drawing. B: Spicules, X 182. The upper one is a 



strongyle, then a curved oxea, then (below) a style. 



as to the possibility that they might be different species. It has been 

 concluded, however, that they are of the same variable species. 



The shape of No. M. 442 is ramose with a single stem and branches, 

 but very few of these branches ever branch again. They are 2 to 4 mm in 

 diameter and reach a total length of 11 cm. The shape of No. M. 443 also is 

 stipitate but tends rather to be fan-like or nabellate. It reaches a height 

 of 11 cm and a diameter of 10 cm. Here, as in the preceding specimen, the 

 point of attachment is only about 1 cm in diameter. The many, many leaf- 

 like portions of No. M. 443 are studded with projections about 3 mm in 

 diameter and from only about 1 mm to perhaps 8 or 10 mm in height. It 

 appears as though each of these projections represents an incipient branch of 

 the sort exemplified to the extreme in Specimen No. M. 442. 



The ectosome and endosome color in life of both specimens was vivid 

 reddish orange, and the consistency was spongy. 



The surface is fairly smooth, but microhispid, and is lipostomous. 



The ectosome is almost exclusively protoplasmic, containing a very few 

 spicules indeed, but those which it does contain project somewhat beyond it. 

 Nearly all of the endosome may be described as consisting of a central axial 

 portion; that is to say, the central axis here comprises most of the trans- 

 verse section of the branch. In No. M. 442, these axial portions appear to 

 be spicular tracts about 400 ju, in diameter. Where the branches are the 

 thickest, this is expanded into a less compact structure. 



The spicules consist of smooth megascleres, some of them styles and 

 others strongyles. Those which occur in the axial region are much curved. 

 In general, the longer spicules are strongyles and the shorter ones are styles, 

 but these two types do not appear to be localized within the sponge. The 

 sizes vary a great deal — some are 2 /x by 200 /x and others 2 fi by 400 fi, 

 some are 4 /u, by 400 /.l and some are 4 fx by 600 p.. 



Burton, 1934, page 565, describing sponges from the Great Barrier 



