88 DEOSERA ROTUNDIFOLIA. [Chap. III. 



which had not as yet become inflected. This latter fact shows 

 that the process of aggregation is independent of the inflection 

 of the tentacles, of which indeed we have other and abundant evi- 

 dence. Again, the exterior tentacles on three leaves were carefully 

 examined, and found to contain only homogeneous purple fluid; 

 little bits of thread were then placed on the glands of three of 

 them, and after 22 hrs. the purple fluid in their cells almost down 

 to their bases was aggregated into innumerable spherical, elon- 

 gated, or filamentous masses of protoplasm. The bits of thread 

 had been carried some time previously to the central disc, and 

 this had caused all the other tentacles to become somewhat in- 

 flected; and their cells had likewise undergone aggregation, 

 which, however, it should be observed, had not as yet extended 

 down to their bases, but was confined to the cells close beneath 

 the glands. 



Not only do repeated touches on the glands* and the contact 

 of minute particles cause aggregation, but if glands, without being 

 themselves injured, are cut off from the summits of the pedicels, 

 this induces a moderate amount of agp-egation in the headless 

 tentacles, after they have become inflected. On the other hand, 

 if glands are suddenly crushed between pincers, as was tried in 

 six cases, the tentacles seem paralysed by so great a shock, for 

 they neither become inflected nor exhibit any signs of aggrega- 

 tion. 



Carbonate of Ammonia. Of all the causes inducing aggrega- 

 tion, that which, as far as I have seen, acts the quickest, and is 

 the most powerful, is a solution of carbonate of ammonia. What- 

 ever its strengtli may be, the glands are always afl"ected first, and 

 soon become quite opaque, so as to appear black. For instance, I 

 placed a leaf in a few drops of a strong solution, namely, of one 



fart to 14G of water (or 3 grs. to 1 oz.), and observed it under a 

 igh power. All the glands began to darken in 10 s. (seconds) ; 

 and in 13 s. were conspicuously darker. In 1 m. extremely small 

 spherical masses of protoplasm could be seen arising in the cells of 

 the pedicels close l)eneath the glands, as well as in the cushions on 

 which the long-headed marginal glamls rest. In several cases the 

 process travelled down the pedicels for a length twice or thrice as 

 gpreat as that of the glands, in about 10 m. It was interesting to 

 observe the process momentarily arrcstetl at each transverse par- 

 tition between two cells, and then to see the transparent contents 

 of the cell next Inflow almost flashing into a cloudy mass. In the 

 lower part of the pedicels, the action i)rocec<led slower, so that it 

 took about 20 m. l>efore the cells halfway down the long marginal 

 and submarginal tentacles became aggregated. 



We may infer that the carbonate of ammonia is absorbed by the 



* Jiidfflns from nn nrconnt of thoy have been excited by a 



M. Hocki'rH oliHorvntlons. which touch nnd have moved; for he 



I have only Jiint won <iiioted In nnyn, " the i-ontcnts of oiwh In- 



the ' ClnrdcnT's Chronicle ' (Oct. (Mvldiitil cell nro oollccfod to- 



10, 1K74), he nnponrH to have pother In the <i*nlre of the cav- 



observofl n Klmllnr phoiumjonon Ity." 

 In the stamens of Rorborl.H, after 



