302 



ANALYTICAL INDEX 



CHAPTER I.— continued. 



Gemmule not an appropriate name, 



Light elicits it from the cell, 



Gemmules escape irregularly, . 



Metamorphosis and foundation of a young specimen, 



Nascent Flustra is a single leaf, 



New margin generated from an old leaf, 



Medium of their connection obscure, 



Do invisible channels permeate the leaf ? 



Plates I., II. explained, 



PAGE 



10 

 11 

 ib. 

 ib. 

 12 

 ib. 

 ib. 

 13 

 ib. 



§ 2. Flustra foliacea, 



Described, .... 



It is thicker than writing paper, 



Both sides cellular, 



Cells adhering horizontally are hexagonal, 



Hydra, ascidian, with 12-14 tentacula, 



Vernacular name, 



Ferruginous patches, cells with gemmules, 



Extraordinary multitude of gemmules, 



Discharged during weeks, 



Their history, 



Metamorphosis, 



Increase of the originating leaf, 



Plates III., IV. explained, 



14 

 ib. 

 ib. 

 ib. 

 ib. 

 15 

 ib. 

 ib. 

 16 

 ib. 

 17 

 18 

 ib. 

 19 



§ 3. Flustra truncata, 



The most luxuriant of FlustraB, 



Both sides of the leaf cellular, 



Hydra? with 12-14 tentacula, 



Nascent hydra in twelve days from the gemmule, 



Plates V., VI. described, 



ib. 



ib. 

 20 

 ib. 

 21 



ib. 



§ 4. Flustra papyracea ? 

 Fine specimen, 

 Plate VII., 

 Dr Grant's valuable observations, 



22 

 ib. 

 ib. 

 ib. 



§ 5. Flustra Murrayana, 



Dr Johnston's denomination preferable, 

 Mode of observing the structure, 

 Only one side of the leaf cellular. 

 Hydra with 14 tentacula, 



23 

 ib. 

 ib. 

 24 

 ib. 



