CRATEROMORPHA CORRTJGATA. 8o 



tangential rays. With these rays they form a fine hypodermal 

 network, the small meshes of which are irregularly angular or 

 are often incompletely enclosed. — The hypodermal diactins are 

 fine and ditter in no way from the smaller parenchymalia. In 

 one specimen of the sponge they were found in tolerable fre- 

 quence ; in others they were rather rare. 



The dermalia (PI. VI., figs. 1 & 2) are rough stauractins 

 and pentactins, the former predominating. Length of ray as 

 measured from the spicular center, 85-138 a. In certain speci- 

 mens I have frequently seen the stauractinic forms in possession 

 of the rudiment of the fifth (proximal) ray in the form of a boss 

 (fig. 2). The four paratangentials of a spicule are in a plane 

 which is but slightly convex on the outside and is often nearly 

 perfectly fiat. The roughness of the ray surface is, as a general 

 matter, less pronounced than in C. meyeri. It often diminishes 

 towards the base of the rays where it is altogethor lost (fig. 1). 



Along the thin oscular margin the dermalia are found to 

 be represented now and then by tauactins and even liy diactins. 

 The latter seem to intergrade with the parenchymalia of the 

 region by forms of intermediate size and character. 



The yastralia are quite like the dermalia. There occur both 

 stauractins and pentactins amongst them, Itut their number must 

 be said to be sparse, being found in scattered distribution. A 

 considerable area of the gastral surface may sometimes be searched 

 in vain for gastralia. 



No special canalaria have been observed. 



The Itexasiera of the species closely agree with those of most 

 other Crateromorpha. They are : 



