SUBJECTS OF EAELIEE LETTEES : 1863-4 217 



Of the remainder, fourteen are holograph letters 

 by Charles Darwin, one (No. 7) is signed and 

 corrected, while three (Nos. 6, 11, 17) are only 

 signed by him. 



The letters are arranged in the order of date. 

 Darwin, as was his custom, omitted to write the 

 year, but fortunately this was nearly always 

 added by Mr. Trimen himself, together with 

 the date at which the letter was received. 



Publications and the names of species, &c., 

 although not underlined in the originals, are, 

 for the sake of convenience, printed in italics. 



The first series of letters, seven in number, 

 deal with botanical subjects, especially Orchids, 

 and the inquiries which grew out of the investi- 

 gations upon them (such as the Peach-perforating 

 moths). These are referred to in all seven letters; 

 Oxalis as material for the study of heterostyled 

 flowers in Nos. 3-7 ; insect visitors to Asdepiadae, 

 Apocyneae, and Physianthus in No. 4 ; the fertili- 

 zation by birds of Strelitzia in Nos. 6, 7. 



It will be observed that Darwin in the very 

 first letter began to urge his correspondent to 

 send home the records of observations for publi- 

 cation. His advice and help were very soon 

 accepted, and, in the Fertilisation of Orchids, 1 

 Darwin acknowledged the assistance he had 

 received, and referred to Trimen's papers, in 

 the publications of the Linnean Society, on Bonatea 

 speciosa and Disa grandiflora, in each case specify- 



1 Second edit., sixth impression (1899), 40, 76-8. 



