740 Transactions of the Society. 



with otLer sets of sections, the results were sometimes less decided ; 

 some of the glands treated with the carbonate remaining unaffected, 

 while a considerable number of those iu the sugar solution showed 

 contraction. 



Ammonia-nitrate and phosphate were also employed, of several 

 strengths, from 1 to |- per cent., using control solutions of cane 

 sugar or gum-arabic, and occasionally distilled water only. 



With ammonia-nitrate the results were altogether negative, a 

 few of the glands only being affected, and about equally in all the 

 sections both in the nitrate and control solutions. 



Ammonia-phosphate in a 1 per cent, solution gave very decided 

 results. Eight sections were placed under covers and examined to 

 see that the glands were in their normal condition. Six of them 

 were then irrigated with the ammonia-phosphate and two with a 

 1 per cent, solution of sugar. 



In two hours a slight increase of granulation was observed in 

 the pedicellated glands of all the sections iu the ammonia-phosphate 

 solution. 



In four hours the protoplasm was slightly shrunken and still 

 more granular. 



In twelve hours the above features were very decided, and the 

 protoplasm much darker in the j)edicellated glands than elsewhere. 



In twenty-four hours the protoplasm was so darkened as to be 

 quite opaque. 



In none of the surface glands did I find the least alteration. 



The sections in sugar solution were nearly unaltered, only very 

 few of the pedicellated glands but retained their normal appearance. 



Other sets of sections were placed in solutions in the proportion 

 of 1 to 200, 400, 800; and in each case the results seemed to point 

 in the same direction, though the changes were neither so rapid 

 nor decided. In sections placed in a 1 per cent, solution of gum- 

 arabic, about half the pedicellated glands showed contraction and 

 granulation, while others placed in water, putrid with decaying 

 vegetation, remained quite unaltered after twenty-four hours. 

 Sections placed in distilled water, after being first washed in it, pre- 

 served their normal appearance at the end of tliirty-six hours ; 

 while others placed in it direct from the razor had about half their 

 glands contracted after the lapse of twenty-four hours. 



These facts, if not amounting to an absolute demonstration of 

 the absorbing function of the pedicellate glands, yet furnish strong 

 presumptive evidence in favour of it. 



We may also infer that seeing the fluid which fills the leaf 

 chambers is acid in character, it must be secreted by the leaf ; and 

 as the sessile surface glands in all the experiments made, remained 

 absolutely unaltered, we may conclude that it is by them that the 

 function is performed. In all probability these functions, viz. 



