VI CONTENTS. 



CHAPTER III. 



Aggregation of the Protoplasm within the Cells of the 

 Tentacles. 



Nature of the contents of the cells before aggregation — Various 

 causes which excite aggregation — The process commences 

 within the glands and travels down the tentacles — Descrip- 

 tion of the aggregated masses and of their spontaneous 

 movements — Currents of protoplasm along the walls of the 

 cells — Action of carbonate of ammonia — The granules in 

 the protoplasm which flows along the walls coalesce with the 

 central masses — Minuteness of the quantity of carbonate of 

 ammonia causing aggregation — Action of other salts of 

 ammonia — Of other substances, organic fluids, &c. — Of 

 water — Of heat — Eedissolution of the aggregated masses — 

 Proximate causes of the aggregation of the protoplasm — 

 Summary and concluding remarks — Supplementary observa- 

 tions on aggregation in the roots of plants . . Pages 33-G5 



CHAPTEK IV. 



The Effects of Heat on the Leaves. 



Nature of the experiments — Effects of boiling water — Warm 

 water causes raj^id inflection — Water at a higher tempera- 

 ture does not cause immediate inflection, but does not kill 

 the leaves, as shown by their subsequent re-exi:)ansion and 

 by the aggregation of the protoplasm — A still higher 

 temperature kills the leaves and coagulates the albuminous 

 contents of the glands 66-75 



CHAPTER V. 



The Effects of Non-niteogenous and Nitrogenous 

 Organic Fluids on the Leaves. 



Non-nitrogenous fluids — Solutions of gum arable — Sugar — 

 Starch — Diluted alcohol — Olive oil — Infusion and decoc- 

 tion of tea — Nitrogenous fluids — Milk — Urine — Liquid 

 albumen — Infusion of raw meat — Impure mucus — Saliva 

 — Solution of isinglass — Difference in the action of these 

 two sets of fluids — Decoction of green peas — Decoction 

 and infusion of cabbage — Decoction of grass leaves 76-84 



