JDH received William Thiselton-Dyer's [WTD's] letter of 13 July [1877] at Denver, Colorado. He is glad WTD is not overwhelmed by the duties of RBG Kew Director in JDH's absence. Mrs Hodgson wrote to JDH about visiting WTD & his wife Harriet Thiselton-Dyer. JDH is working learning a lot about western conifers, especially the Pines of Colorado, which are very diverse & incl. Pinus edulis, P. ponderosa P. aristata, P. flexilis, Abies douglasii, A. menziesii, A. engelmannii, Picea concolor, Juniperus virginiana, J. occidentalis & J. communis. Of these western American species only the Junipers are found East of the Rocky Mountains. JDH has collected 500 species. Next the party travels East to the Wahasatch [Wasatch] Mountains beyond Salt Lake to get a glimpse of the West Colorado vegetation where Pinus edulis gives way to P. monophylla. They will go to Nevada & the Taxodium grove via Carson & Silver City then via Calavera & Mariposa to San Francisco, the Redwood [Sequoioideae] district & Monterey. JDH's travelling companion Asa Gray should write a general description of the botanical geography of North America, they may write something jointly for Hayden's Survey. The Stracheys are good company. Discusses improvements being made at RBG Kew: replacement of the boilers [in the Palm House] with 'Rivers' Boilers', the controversy over the height of the [RBG Kew boundary] wall, bad work done by a contractor & poor foundations of the Palm House. JDH is anxious to give up his duties at the Royal Society & focus on RBG Kew. JDH has seen the RBG Kew report published in THE DAILY TELEGRAPH. Mentions news regarding his sons Charles Paget Hooker & Brian Harvey Hodgson Hooker. JDH is suffering with diarrhoea & travelling through wilderness has left him bruised. He does not have the energy he once had, though he did climb Gray's Peak to 14,300 feet. Recounts the feeling of being at the top of the peak during an electrical storm with Mr Darrell, son of Judge Darrell of Bermuda.