i868 i88i] UTRICULARIA 403 



Now for your letter : you are very generous about Dioncca, Letter 726 

 but some of my experiments will require cutting off leaves, 

 and therefore injuring plants. I could not write to Lady 

 Dorothy [Nevill]. Rollisson says that they expect soon a 

 lot from America. If Dionoea is not despatched, have marked 

 on address, " to be forwarded by foot- messenger." 



Mrs. Barber's paper l is very curious, and ought to be 

 published ; but when you come here (and remember you 

 offered to come) we will consult where to send it. Let me 

 hear when you recommence on Cephalotus or Sarmcenia, as 

 I think I am now on right track about Utricularia, after 

 wasting several weeks in fruitless trials and observations. 

 The negative work takes five times more time than the 

 positive. 



To J. D. Hooker. Letter 727 



Down, Sept. i8th [1874]. 



I have had a splendid day's work, and must tell you 

 about it. 



Lady Dorothy sent me a young plant of U\tricularia~\ 

 montana* which I fancy is the species you told me of. The 

 roots or rhizomes (for I know not which they are ; I can see 

 no scales or internodes or absorbent hairs) bear scores of 

 bladders from -^ to T Jo of an inch in diameter ; and I traced 

 these roots to the depth of ij in. in the peat and sand. The 

 bladders are like glass, and have the same essential structure 

 as those of our species, with the exception that many exterior 

 parts are aborted. Internally the structure is perfect, as is 

 the minute valvular opening into the bladder, which is filled 

 with water. I then felt sure that they captured subterranean 

 insects, and after a time I found two with decayed remnants, 

 with clear proof that something had been absorbed, which had 

 generated protoplasm. When you are here I shall be very 

 curious to know whether they are roots or rhizomes. 



Besides the bladders there are great tuber-like swellings 

 on the rhizomes ; one was an inch in length and half 

 in breadth. I suppose these must have been described. I 



1 Mrs. Barber's paper on the pupa of Papilio Nirens assuming 

 different tints corresponding to the objects to which it was attached, 

 was communicated by Mr. Darwin to the Trans. Rntomolog. Soc., 1874. 



2 See Life and Letters, III., p. 327, and Insectivorous Plants, p. 431. 



