R. PHŒNIX. — SPICULATION. 273 



pentactins as tlie principal parenchymalia of the species. Later 

 ('99) he described for these strong oxydiactiiis bent in a 

 boomerang-like manner. This apparent contradiction may be 

 explained by assuming that on the first occasion he had before 

 him the above-described oxypentactin of the marginal zone, which 

 assumption is all the more likely since at the time only the 

 upper end of the body was available for his study. 



The dermalia (PL X, figs. 23, 24) — as they occur on the 

 general surface, forming a delicate, quadrate-meshed latticework, 

 the meshes measuring only about 240/-« in length of sides — are 

 small, slender-rayed hexactins in which tlie distal ray is the 

 shortest and the proximal ray, usually but not always the longest 

 of all the rays. The former is only GO-90 /.« long and scarcely 

 ever exceeds G// in thickness. It slightly broadens towards the 

 rounded outer end, but never to such a marked degree as to give 

 it a distinctly club-like form. The surface is rather sparsely 

 provided with almost obsolete microtubercles. All the other rays 

 taper gradually toward the bluntly pointed end. Tiiey are 

 smooth all over or subterminally faintly rough ; straight or some- 

 Avhat bent. The paratangentia.ls are 150-230 /i long. The prox- 

 imal ray is, as indicated above, usually much longer (fig. 23), 

 but sometimes only about as long ; it may even be considerably 

 shorter (fig. 24), as, for instance, in those dermalia situated on the 

 membranous edge of the parietal oscula. 



Dermalia of the above description have been hitherto un- 

 known from the species and constitute one of the points which 

 it is exceedingly desirable should be tested in specimens from 

 the Atlantic. 



