132 Mr. H. J. Carter on the 



CERATINA. 



Family 1. Luffarida. 

 Rigid fibre, with opaque, white, granular core mostly 

 hollow. 



Family 2. Aplysinida. 



Subrigid or flaccid fibre, with wide, hollow, granular core. 



Family 3. Pseudoceratida. 



Fibre of either of the foregoing families sparsely cored with 

 foreign bodies — or passing into a dermal layer of foreign 

 bodies, or one of " proper spicules " like that of the Rhaphi- 

 donemata. 



PSAMMONEMATA. 



Family 1. Bibulida*. 



Solid fibre chiefly without core of foreign objects. 



Family 2. Hircinida. 



Solid fibre chiefly cored with foreign objects. 



Family 3. Pseudohircinida. 



Solid fibre cored with foreign objects and proper spicules, 

 sometimes also echinated with proper spicules. 



RHAPHIDONEMATA. 

 Family 1. Chalinida. 



Digitations solid, vertical or procumbent. 



Family 2. Cavochalinida. 



Tubular, vasiform, aculeated patulous, or compressed flabel- 

 lately ; plane and frondose or dactyloid. 



Orders with any likelihood of certainty. Hence I now propose to divide 

 them, after these orders, into Families and Groups provisionally, which, 

 on a better acquaintance with the species, might be changed to Suborders 

 and Families as the occasion may require. 



Where, however, among the Groups I have to a certain extent been 

 able to anticipate this change, each has been named after a typical genus ; 

 but where no typical species has yet been described, the Group has been 

 named adjectively after its most striking characters. 



* This family has been placed among the Psammonemata, because I 

 have never failed in good specimens to find here and there a fibre cored 

 with foreign bodies. But as this is likely to escape observation from its 

 scantiness, I have given the family the character of " simple solid fibre," 

 although I cannot, from the fact mentioned, make it an order. 



