To William Hutton 30 January 1840

My dear Sir,

I wish much to see an authentic specimen of Pecopteris heterophylla Pl.38. I have some beautiful specimens (of Sedgwick's) of what I consider to be decidedly P. Mantelii from the Felling Colliery, but the veins are forked like those of all the allied species excepting heterophylla - & I suspect that there must be some mistake in that instance.

I cannot find any of the lobes of the pinnules or pinnulae of Pecop. Lonchitiea (plate 153) so much pointed as they are represented to be in the Syl.2.A. Brong.ts 83 Pl a are very different!

Pray don't let me bother you to answer every quere I send - but if I neglect to make a mem. at the time. I may perhaps forget what I wish to ask you. My chief object was to secure attention in case you were transmitting specimens. In future I shall keep a sheet for memoranda, & not forward it till I know when you are about to send me a box, & I can then let you know my wishes. I have no doubt about the blunt straight extremities of calamites being the bases of stems with roots as at Pl.78&79 & it was from Pl.22 of C. mongeottii that I felt convinced that the curved extremities were all bases of branches - which I can no where find asserted. By the by, Sternbergh has referred to the fractured branch of your C. mongeottii as a proof of a dichotomy! The joint above fractured in opposite direction clearly shows what it is. I had suspected Artis's Filicites osmundae to be a portion of N. heterophylla but afterwards considered it must be distinct & altogether new - no way allied to C. Beanii but closely so to N. Villiersii. I have not heard from Brongniart & fear my letter must have miscarried. I think I told you that I had received some drawings of a new Stigmaria from the Leeds Society - with a description - & which I think will answer your purpose very well. I wish I could spend a week in the Coal Mines myself - it would enable me to form a more correct judgment which rather, or not rather, puzzle me at present. Pray don't trouble yourself to answer me merely because I write. I was surprised to see the date of your letter the 28th till I saw the postmark was 27th as I could not imagine how I cd receive it in 2 days.

Yrs very truly

J. S. Henslow

How does the Structure of Coal progress?