Chap. XV.] CONCLUDING REMARKS. 277 



solved, but this may have been a mistake. A second, when 

 examined after 17 hrs. 25 m., was liquefied, but the liquid 

 as seen under the microscope still contained floating gran- 

 ules of fibrin. The other two shreds were completely lique- 

 fied after 21 hrs. 30 m. ; but in one of the drops a few 

 granules could still be detected. These, however, were dis- 

 solved after an additional interval of 6 hrs. 30 m. ; and the 

 surface of the leaf for some distance all round was covered 

 with limpid fluid. It thus appears that Drosophyllum di- 

 gests albumen and fibrin rather more quickly than Drosera 

 can; and this may perhaps be attributed to the acid, to- 

 gether probably with some small amount of the ferment, be- 

 ing present in the secretion, before the glands have been 

 stimulated; so that digestion begins at once. 



Concluding Remarks. The linear leaves of Drosophyl- 

 lum differ but slightly from those of certain species of 

 Drosera; the chief differences being, firstly, the presence of 

 minute, almost sessile, glands, which, like those of Dionaea, 

 do not secrete until they are excited by the absorption of 

 nitrogenous matter. But glands of this kind are present on 

 the leaves of Drosera hinata, and appear to be represented by 

 the papilla3 on the leaves of Drosera rotundifolia. Secondly, 

 the presence of tentacles on the backs of the leaves; but we 

 have seen that a few tentacles, irregularly placed and tend- 

 ing towards abortion, are retained on the backs of the leaves 

 of Drosera hinata. There are greater differences in function 

 between the two genera. The most important one is that 

 the tentacles of Drosophyllum have no power of movement; 

 this loss being partially replaced by the drops of viscid se- 

 cretion being readily withdrawn from the glands; so that, 

 when an insect comes into contact with a drop, it is able 

 to crawl away, but soon touches other drops, and then, smoth- 

 ered by the secretion, sinks down on the sessile glands and 

 dies. Another difference is, that the secretion from the 

 tall glands, before they have been in any way excited, is 

 strongly acid, and perhaps contains a small quantity of the 

 proper ferment. Again, these glands do not secrete more 

 copiously from being excited by the absorption of nitroge- 

 nous matter; on the contrary, they then absorb their own se- 

 cretion with extraordinary quickness. In a short time they 

 begin to secrete again. All these circumstances are prob- 



