From J. D. Hooker   22 December 1858

My dear Darwin

I am & have been working hard at my Essay & make about as slow progress as you say you do.¹ I am utterly staggered by some of the facts of distribution—here is wild rice & lots of other plants identical with Indian, in N.W. Australia several hundred miles from the coast, & there is a most typical American plant (not found in India) from the same locality. I have now got together about 500 tropical Indian species in Australia, many of them very peculiar besides many generic types almost all Peninsular: Indian, not Malayan or Javanese types—but plants of the sandstone ranges of Australia & India. Now though there are several wet country Australian types (not species) in Malayan Islands & Peninsula, there are none in the Indian Peninsula, nor are there any of the hundreds of Australian Sandstone & dry tropical types in the Indian Peninsula. Now I never can believe that 500 Indian plants got transported by existing causes to tropical Australia, & that the said causes did not return one tropical Australian Acacia, Eucalyptus, Stylidium, Proteacea, Goodenia, Casuarina or Restiacea &c to the Indian Penin-sula!—²

Weeds, herbs, shrubs & trees of many Indian families have gone S.E. to Australia & nothing has gone back N.B. Eucalypti, Casuarina & acacias grow magnificently all over the Peninsula where planted & ripen loads of seed.

You kindly promised me the loan of your Chapter on transmigration of forms across tropics & I should be glad of it.³ I am grievously troubled to know at what date to assume this transmigration Am I safe in assuming that the Antarctic types entered Australia at same epoch—& what was general character of Australian Flora at that epoch.⁴ Jukes I find speculates in his sketch on Australia being 2 groups of Islands; was your review of Waterhouse anterior to this? ⁵

Highlands of Abyssynia will not help you to connect the Cape & Australian temperate Floras; they want all the types common to both & worse than that, India notably wants them—Proteaceæ, Restiaceæ, Thymeleaæ, Hæmodoraceæ, Acacia, & Rutaceæ of closely allied genera (and in some cases species) are jammed up in S.W. Australia & C.B.S.—⁶ Add to this the Epacrideæ (which are mere § of Ericeæ), & the absence or rarity of Rosaceæ &c &c &c & you have an amount of similarity in the Floras, & dissimilarity to that of Abyssynia & India in the same features that does demand an explanation in any theoretical history of Southern vegetation.

I still hold to a large Southern Continent characterized by these & the Ant-arctic types—⁷ Perhaps during the Cretaceous & Oolitic periods some of these types existed in the N. Hemisphere also—hence the Araucaria cones in Oolite, Banksia wood of the sands at Chobham (what age are they?) & cretaceous fossils supposed to be Proteaceae in Belgium &c.???

Are all the coal & Sandstone fossils of Australia Palæozoic? & is there in Australia a gap in the Geolog series between these & modern tertiary beds? ⁸

I also still regard plants types as older things than animal types— I have a fossil Araucaria cone from the Oolite identical to all appearances with A. excelsa of Norfolk Island & the Chobham fossil Banksia wood is identical with Tasmanian: I do not suppose specifically in either case, but that such highly organized types should be so similar, indicates a great age for them as types.

We went to the Whewells at Trinity Lodge for 4 days⁹ & my wife enjoyed it much, she has been laid up with Influenza ever since & I am now in for it.

I am going to Ld Wrottesley’s for a few days on the 5^th to meet Bell & Brodie Miller & Sharpey.¹⁰

I have today been informed that the W. & F. have spontaneously determined to increase my salary to £500 & let me have my house rent free, which are very acceptable bonus.¹¹ they will also put the house in complete repair, but I must add to it if I want at my own cost.— Now I want to add two such rooms as yours only smaller—say 15 x 20.— What did yours cost you?¹²

Ever Yrs | Jos D Hooker