CALCAREOUS SPONGES, 765 



The only known species is : — 



1. S. HYSTKix Haeckel. 



Sycandra hystrix Haeckel [1872]. 



Genus 30. Achramorpha Jenkin [1908 B] (emend.). 



Diagnosis. Canal system syconoicl. Skeleton of the chamber 

 layer reduced to the basal rays of the subgasti-al sagittal 

 triradiates (which may become quadriradiates by the addi- 

 tion of an apical ray), with radial oxea lying between the 

 chambers and projecting from the surface. No colossal 

 longitudinal oxea. 



For illustrations of this genus see Jenkin [1908B] ; and Breitfuss 

 [1898 D] under Ebnerella schulzei. 



This genus was proposed by Jenkin for the three species 

 glacialis, grandinis and nivalis, which resemble one another 

 closely, and which all possess the so-called chiactines of his 

 supposed family Staurorrhaphidte. The fact that another species, 

 Breitfuss's Ebnerella schidzei, differs in no essential point except 

 the absence of chiactines, affords strong evidence for our view 

 that the latter are nothing but subgastral sagittal triradiates 

 that have developed apical rays, and therefore not even of generic 

 importance, since such spicules are known to occur in other 

 Grantiidae. These species, however, form a well-defined grovip, 

 and we accordingly retain the generic name Achramorpha, with 

 an emended diagnosis based upon what we believe to be more 

 important characters. 



We assign the following species to the genus : — 



Section A. With microxea. 



1. A. glacialis Jenkin. 



Achraonorpha glacialis Jenkin [1908 B]. 



2. A. GRANDINIS Jenkin. 



Achramorpha grandinis Jenkin [1908 B]. 



3. A. NIVALIS Jenkin. Type species of the genus. 



Achraiiiorpha nivalis Jenkin [1908 B]. 



4. A. SCHULZEI Breitfuss. 



Ebnerella schulzei Breitfuss [1896 A]. 



Section B. Without microxea. 



5. A. TRUNCATA Topscnt. 



Grantia truncata Topsent [1907]. 



