The specialised types are all Arctogeal with the exception of half a dozen or so Andean species including prostrata.
There is a strange general parallelism with the crayfishes! which also have their primary forms in Australia and New Zealand, avoid E. S. America and Africa, and become most differentiated in Arctogaea. But there are also differences in detail.
It strikes me that this is uncommonly interesting; but, of course, all the information about the structure of the flowers, etc., I get at second hand, wants verifying.
Have you done the gentians of your "Flora Indica" yet? Do look at them from this point of view.
I cannot make out what Grisebach means by his division of Chondrophylla. What is a "cartilaginous" margin to a leaf?—"Folia margine cartilaginea!" He has a lot of Indian species under this head.
I send you a rough scheme I have drawn up. Please let me have it back. Any annotations thankfully received. Shan't apologise for bothering you.
I hope the pension is settled at last.
Ever yours,
T.H. Huxley.
4 Marlborough Place, September 22, 1886.