276 lETTEES PEOM C. DARWIN, ESQ., 



the classification of Alcippe. I have been very troublesome, but 

 shall cause no more ; and am truly obliged for all you have done 

 for me. If in your power I am sure you will kindly in course 

 of summer get me a few specimens for the British Museum and 

 for distribution. 



I yet have a few specimens of other Cirripedes of yours in my 

 possession. 



I have now finally finished with my South American Boriug 

 Cirripede ; and this has utterly confounded my previous confu- 

 sion how to rank Alcippe and it; for they present some most 

 remarkable similarity, for instance, they are both bisexual, with 

 the males remarkably alike, and yet, in what I must consider 

 their fundamental organization, and in their metamorphosis, they 

 are so totally unlike that I cannot place them in the same orders! 

 My classification does not satisfiy myself, nor, I fear, you, if ever 

 you look to my volume on this point. 



Pray believe me, my dear Sir, 



Yours truly obliged, 



Ch. Daewin. 

 The bosses on the rim of Alcippe are hardish or crustaceous, 

 they are all four opposed to each other, and the little ridges on 

 them are crenated. These facts made me suspect that their use 

 was not for simple prehension but for triturating the food ; and 

 now I find in my analogous South American burrower, and in no 

 other Cirripede, that the oesophagus is provided with the most 

 beautiful discs, set with teeth, and brushes of hairs, worked by 

 muscles, certainly for triturating food, which strengthens my 

 notion. 



No. 19. 



Down Farnborough, Kent, 



Aug. 24th, 1854. 

 My dear Sir, 



You may remember that you gave me permission most 



generously to dissect all your specimens of Alcippe lampas, which 



