500 CLIMBING AND INSECTIVOROUS PLANTS. [1875. 



bladders shrink and contain air instead of water ; I shall 

 then also wash all earth from all roots, and see whether there 

 are true bladders for capturing subterranean insects down to 

 the very bottom of the pot. Now shall you think me very 

 greedy, if I say that supposing the species is not very pre- 

 cious, and you have several, will you give me one more plant, 

 and if so, please to send it to " Orpington Station, S. E. R., 

 to be forwarded by foot messenger." 



I have hardly ever enjoyed a day more in my life than I 

 have this day's work ; and this I owe to your Ladyship's 

 great kindness. 



The seeds are very curious monsters ; I fancy of some 



plant allied to Medicago, but I will show them to Dr. 



Hooker. 



Your Ladyship's very gratefully, 



Ch. Darwin. 



C. Darwin to J. D. Hooker. 



Down, September 30, 1874. 



My dear H., — Your magnificent present of Aldrovanda 

 has arrived quite safe. I have enjoyed greatly a good look 

 at the shut leaves, one of which I cut open. It is an aquatic 

 Dionaea, which has acquired some structures identical with 

 those of Utricularia ! 



If the leaves open and I can transfer them open under 

 the microscope, I will try some experiments, for mortal 

 man cannot resist the temptation. If I cannot transfer, I 

 will do nothing, for otherwise it would require hundreds of 

 leaves. 



You are a good man to give me such pleasure. 



Yours affectionately, 



C. Darwin. 



[The manuscript of 'Insectivorous Plants' was finished 

 in March 1875. ^^ seems to have been more than usually 

 oppressed by the writing of this book, thus he wrote to Sir 

 J. D. Hooker in February : — 



