CALCAREOUS SPONGES. 777 



Section A. Withovit microxea. 



1. A. ALCicoRNis Gra]i. Type species of the genus. 



Aphroceras cdcicornis Gray [1858]. 



Cyathiscus actinia, Haeckel [1870],_/i(Ze Haeckel [1872]. 



Leucandra alcicornis Haeckel [1872]. 



2. A. CATAPHRACTA Ilasckel. 



Leucandra cataphracta Haeckel [1872]. 



3. A. ELONGATA Scliuffncr. 



Leucandra elongata Schufiher [1877]. 



Section B. Witli microxea. 



4. A. CiESPiTOSA Haeckel. 



Leucandra alcicornis var. ccespitosa Haeckel [1872]. 



5. A. CLiARENSis Stephens. 



Leucandra cliarensis Stephens [1912]. 



6. A. CORTICATA von Lendenfeld. 



Vosmaeria corticata von Lendenfeld [1891]. 



Genus 39. Leucettaga Haeckel [1872] (emend.). 



Diagnosis. Canal system leuconoid. Skeleton almost entirely 

 composed of a confused mass of triradiates, which are mostly 

 irregular and which form the dermal cortical skeleton as 

 well as the skeleton of the chamber layer. Gastral cavity 

 traversed by numerous endogastric septa, which possess a 

 special skeleton of their own in the form of minute radiates. 



For illustrations of this genus see Haeckel [1872]. 



This genus is proposed for the reception of Haeckel's Leucetta 

 2)andora var. loculifera, which is the only known species. It 

 affords an example amongst leuconoid Calcarea of that remarkable 

 development of endogastric septa which occuis also in certain 

 Leucosolenias (e. g. L. wilsoni) among the Homocoelidse, in 

 Leucettusa among the Leucaltidse, and in Sycandra among tlie 

 SycettidfB. We have, however, only considered it necessary to 

 attribute generic importance to this character when it is combined, 

 as in the present instance, with the presence of an endogastric 

 skeleton. 



We haA^e revived this name, which was applied by Haeckel to 

 one of the subgenera of his Leucetta, for this genus. 



The only known species is : — 



1. L. loculifera Haeckel. 



Leucetta pandora \a.v. locidifera Haeckel [1872]. 



