

EXPLANATION OF PLATE IV. 



Fig. 1. Spicules of Mopsea plumacea, sp. nov. ; from the 

 specimen figured on Plate vii. 



Fig. 2. 8picules of Mopsea repens, sp. nov. ; from the 

 specimen figured on Plate viii. 



Fig. 3. Spicules of Plumarella australis, sp. nov. ; from the 

 specimen figured on Plate x. 



Fig. 4. AmphilapM* plumacea, Thomson and Mackinnon. 

 Photograph of a specimen 17-5cm. in height, from 

 the M>uth east coast of Australia. 



Fig. 5.- Ctenocella pectinata (Pallas). Branches showing 

 distinct median furrow. Photograph of a specimen 

 from eight miles east of Sandon Bluff, Queensland, 

 35-40 fathoms. 



