214 THE SPONGES OF THE WEST-CENTRAL PACIFIC 



but the larger fibers are often more than 2 mm apart. These tracts might 

 contain some spongin but largely are densely packed with spicules, which are 

 in somewhat plumose arrangement. Some of them seem actually to echinate 

 the fibers. Nearly all the spicules have their points arranged towards the 

 surface of the sponge. 



The skeleton has already been described partially in connection with 

 remarks about the endosome. In addition to the tracts, however, mention 

 should be made of the spiculation. This consists of monaxon megascleres 

 exclusively. These vary in a curious way from styles to subtylostyles. Appar- 

 ently there is no significance whatever to which occurs in whatever location. 

 Some specimens seem to have only the subtylostyles, some specimens have 

 all or nearly all styles, and in other cases there is an intermingling of the two 

 types. None are ever typically or pronouncedly tylostylote. Maximum sizes 

 per specimen range from 13 ^ by 490 fi to 9 p. by 820 fi. All sizes below this 

 may be found, evidently due to growth stages. 



This species was first described as H ymeniacidon agminata by Ridley, 

 1884, page 466, from Australia, and designated as type of Stylotella by Hall- 

 man, 1914, page 349. Hallman also quite properly referred other species in 

 synonymy to agminata, so that this sponge has a very considerable published 

 range throughout the Australian region. It is here considered probable that 

 all species hitherto referred to the genus Stylotella are either synonyms of 

 agminata or incorrectly located and worthy of transferral to various other 

 genera. A complete revision is not, however, undertaken at the present time. 



GENUS CRYPT AX, new 



This genus is here established as in the family Suberitidae only with very 

 considerable doubt, because there are many indications that it should belong 

 instead in the family Clionidae. Inasmuch as that is the ensuing family, the 

 present location between the two is as nearly appropriate as possible at the 

 moment. The type of this genus is here established as the following species 

 Cryptax orygmi. This is a genus of sponges occurring completely buried in 

 excavations within calcareous material, but it is not at the present time at all 

 certain that the excavations were made by the sponge which now inhabits 

 them. Instead it may merely be moving into quarters which had been pre- 

 pared by other organisms. The spiculation is also noteworthy, consisting 

 exclusively of tylostrongyles. 



The genus name suggests the buried habitat. 



Cryptax orygmi, new 



Text Figure No. 146 



This species is here represented by the following : 

 U.S.N.M. No. 22966, My No. M. 340, here designated as type, collected 



