﻿152 "ENDExWOUE" SCIENTIFIC RESULTS. 



ture of the skeleton to distinguish it generically I'rom certain 

 species at present inckided in the genus Axiuellu. 



The three sponges described by Lendenfeldi under the namc 

 ol Echinonema anchoniium. Carter, have, according to their 

 description, the spiculation of Clatlnissa, but the skeleton is 

 reticulate. The best plan to adopt in regard to these sponges 

 is to regard them as species cluhice of WihoncJUt [g-v.]. 



Genus Creela, Gray. 

 Thiele2 has expressed the opinion that Pluuiohalichondria 

 iucnistans, Carter, should be placed in the genus Pytheus 

 which, as Lundbeck has recently shown, must now be called 

 C reiki. Accordingly I employ the latter name for the sponges 

 about to be described. These agree so closely in the charac- 

 ters and dimensions of their spicules that, despite considerable 

 differences in some other respects, they might very well be 

 treated — in contrast with other species of the genus — as 

 \'arieties of a single species, Crella incrustans. In this species, 

 as in Clathrissa arbuscuhi the smooth oxeote spicules are 

 secondarily diactinal. 



Crella incrustans. Carter, et varr. 

 (Plate xxiii., Hgs. 2, 3; Plate xxiv. ; and hgs. 28-34.) 



Creiieral diagnosis : Kxienud form various: encrustiiig, 

 massive or ramose. Oscida present in probably all the 

 varieties. Typically {^utdess in encrusting varieties) the 

 branching ascendent fdires of the main skeleton are 

 sinuous and interosculate so as to form a kind, of loose 

 reticulation (pseudo-reticulation) ; connecting fibres, in 

 small number, may occur. The fibres are fairly closely, 

 sometimes extremely densely, echinated with straight 

 conical acantho style s ; the coring spicules may he exclu- 

 sively smooth oxea, or exclusively acantho styles, or a 

 mixture of both. Foreign particles are in some cases 

 included in the fibres. The dermal skeleton is a layer of 

 shorter {usually slightly curved) acanthostyles, with a 

 reticidate or more or less confused arrangement, rarely 

 accompanied by relatively few smooth oxeotes. All three 

 kinds of megascleres occur interstitially, the dermal acan- 

 thostyles typically in greatest abundance. The micro- 

 scleres are of a single kind, isochelcB arcuatce, scattered 

 interstitially and in the dermal layer in moderate abund- 



1 Leiidenfeld-Cat. Sponges Austr. Mus., 1888. p. 219. The three sponges 

 referred to bear the varietal names, ramosa, dura and lameUosa. Their 

 type-specimens appear to have been lost, since the specimen.s which 

 Whitelegge regarded as such cannot at all be reconciled with 

 Lendenfeld's descriptions U'ide Appendix). 



2 Thiele— Archiv. Naturg.. 1903. p. 388. 



