402 BOTANY [Chap. XI 



Letter 725 I have ascertained this morning that the protoplasm in the 

 glands beneath the little leaves has undoubtedly undergone 

 aggregation. Therefore, absurd as it may sound, I am pre- 

 pared to affirm that Pinguecula is not only insectivorous, but 

 graminivorous, and granivorous ! Now I want to beg you to 

 look under the simple microscope at the enclosed leaves and 

 seeds, and, if you possibly can, tell me their genera. The 

 little narrow leaves l are remarkable ; they are fleshy, with 

 the edges much curled from the axis of the plant, and bear 

 a few long glandular hairs ; these grow in little tufts. These 

 are the commonest in Pinguicula, and seem to afford most 

 nutritious matter. A second leaf is like a miniature sycamore. 

 With respect to the seeds, I suppose that one is a Carex ; the 

 other looks like that of Rumex, but is enclosed in a globular 

 capsule. The Pinguicula grew on marshy, low, mountainous 

 land. 



I hope you will think this subject sufficiently interesting 

 to make you willing to aid me as far as you can. Anyhow, 

 forgive me for being so very troublesome. 



T , „ , To J. D. Hooker. 



Letter 726 J 



Down, Aug. 30th [1S74]. 



I am particularly obliged for your address. 2 It strikes 

 me as quite excellent, and has interested me in the highest 

 degree. Nor is this due to my having worked at the subject, 

 for I feel sure that I should have been just as much struck, 

 perhaps more so, if I had known nothing about it. You 

 could not, in my opinion, have put the case better. There 

 are several lights (besides the facts) in your essay new to 

 me, and you have greatly honoured me. I heartily con- 

 gratulate you on so splendid a piece of work. There is a 

 misprint at p. 7, Mitschke for Nitschke. There is a partial 

 error at p. 8, where you say that Drosera is nearly indifferent 

 to inorganic substances. This is much too strong, though 

 they do act less efficiently than organic with soluble 

 nitrogenous matter ; but the chief difference is in the widely 

 different period of subsequent re-expansion. Thirdly, I did 

 not suggest to Sanderson his electrical experiments, though, 

 no doubt, my remarks led to his thinking of them. 



1 Those of Erica tetralix. 



2 Presidential address (Biological Section) at the Belfast meeting of 

 the British Association, 1874. 



