BY R. VON LENDENFELD, PH.D. 339 



3. FAMILY LEUCONIML 



Calcispongise with thick walls, which are traversed by ramified 

 canals, which are partly in connection with the Oscular tube, and 

 partly with the pores. Small ciliated chambers connect the two 

 systems of canals. 



II. ORDO MYXOSPONGI^]. 



SPONGI^E WITHOUT ANY SKELETON, OR WITH ONLY FEW 

 AND SCATTERED SILICIOUS BODIES. 



1. FAMILY HALISARCID^E. 



Myxospongite. The ground substance without a fibrillous 

 structure. 



2. FAMILY CHONDROSIDiE. 



Myxospongise the ground substance of which is tough, and has a 

 fibrillous structure. 



1. SUB-FAMILY CHONDROSIN^E. 

 Chondrosidse without Flesh spicules. 



2. SUB-FAMILY CHONDRISSIN^E. 

 Chondrosida? with Flesh spicules. 



III. OBDO CERAOSPONGLE. 



SPONGI^E WHICH POSSESS A SKELETON COMPOSED OF 

 HORNY FIBRE, WHICH MAY CONTAIN FOREIGN BODIES BUT 

 NEVER PROPER SPICULES. SILICEOUS BODIES RARELY DE- 

 VELOPED AS SMALL SCATTERED SPICULES IN THE GROUND 

 SUBSTANCE. 



