ANALYTICAL INDEX. 



Ill 



CHAPTER \ .—continued. 



A whitish spherules in substance, swim with a vertical motion, 

 Plate XXII. described, .... 



ib. 



Spongia mammillaris (Halichondria mammillarkj , . . I'd 



Cannot identify it with Dr Johnston's works, . . ib. 



Invested a shell, ...... ib. 



Measurementj &c., ...... ib. 



MUller's specimen inferior, ..... ib. 



Plate XXIII. described, ..... ib. 



Spongia? . . • • • • • 91 



Rooted on a small shell of the Venus Islandica, . . . ib. 



Measurement and form described, .... ib. 



This product forms a vortex, caused possibly by expulsion and 



absorption, ...... ib. 



Plate XXIV. described, ..... 92 



Halichondria oculata, ..... 93 



Specimen brought in November 1832, ... ib. 



Measurement, ....... ib. 



Of an umber colour, ..... ib. 



Plates XXV. XXVI. described, . . . . ib. 



ADDENDA, 97 



LiSSOTRITON PUNCTATUS Ncwt Or Eft, ... ib. 



Notes found among Sir John's papers in reference to the above, ib. 



Plate XXVII. described, ..... 99 



VOL. III. 



