110 DEOSEEA ROTUNDIFOLIA. Chap. VI. 



re-expand, the rest being much injured or killed. I 

 repeated the experiment, but moistened the phosphate 

 with saliva to insure prompt inflection ; one leaf re- 

 mained inflected for six days (the little saliva used 

 would not have acted for nearly so long a time) and 

 then died; the other leaf tried to re-expand on the 

 sixth day, but after nine days failed to do so, and 

 likewise died. Although the quantity of phosphate 

 given to the above four leaves was extremely small, 

 much was left in every case undissolved. A larger 

 quantity wetted with water was next placed on the 

 discs of three leaves ; and these became most strongly 

 inflected in the course of 24 hrs. They never re-' 

 expanded ; on the fourth day they looked sickly, 

 and on the sixth were almost dead. Large drops 

 of not very viscid fluid hung from their edges during 

 the six days. This fluid was tested each day with 

 litmus paper, but never coloured it ; and this cir- 

 cumstance I do not understand, as the superphosphate 

 of lime is acid. I suppose that some superphosphate 

 must have been formed by the acid of the secretion 

 acting on the phosphate, but that it was all absorbed 

 and injured the leaves ; the large drops which hung 

 from their edges being an abnormal and dropsical 

 secretion. Anyhow, it is manifest that the phos- 

 phate of lime is a most powerful stimulant. Even 

 small doses are more or less poisonous, probably on 

 the same principle that raw meat and other nutri- 

 tious substances, given in excess, kill the leaves. 

 Hence the conclusion, that the long continued in- 

 flection of the tentacles over fragments of bone, 

 enamel, and dentine, is caused by the presence of 

 phosphate of lime, and not of any included animal 

 matter, is no doubt correct. 



Gelatine, — I used pure gelatine in thin sheets given 



