WCP2272

[1]

42 Pine S^t. New York

15^th. May 1871

Dear Sir,

By this mail, I send you copies of a couple of papers of which I am the author, one of which, that on the Physical Geography ^&c. of certain of the West India Islands, will I think especially interest you.¹ I mentioned to my friend M^r. J[ohn]. H[oward]. Redfield² of Philadelphia, with whom I think you have correspondence, that I should take this step, and in a letter just received from him, he urges me to do so.

I may mention that for some years the subject of the geographical distribution of Terrestrial Mollusks in the West Indies has engaged my attention and from time to time I have published the results of my inquiries.

I resided for some time in Jamaica, also in Barbados and S^t. Thomas, — knowing personally or corresponding with most of the Naturalists in the Islands I have had peculiar facilities for obtaining specimens.

Governor Rawson³ and I are now preparing for publication a Catalogue of species with further notes on their distribution. [2]

About a year ago I took up [the] subject of the depth of water in the Caribbean Seas, and discussing the matter with Professor Baird⁴ and M^r. Lawrence,⁵ both distinguished ornithologists, was referred to your work on the Malay Archipelago.⁶

I read it with great interest, — it really opened to me a new field, and shewed⁷ me the value of the line of inquiry upon which I had entered. I communicated this to my friend Gov. Rawson, and he fortunately obtained the results of the labors of the Telegraph Cable people. To you, then, should I especially send a copy of the paper referred to.

In every point of view the study of the distribution of the Land Shells seems to be of value.

Geologically, so far as I know, they are of comparatively recent existence. Their habits preclude distribution by many of the means to which the distribution of Vertebrates may be attributed. Marine Mollusks have, as may be expected, a wider range. The Caribbean marine fauna, as shewn both by fossil and [3] recent shells is one and the same.

The "fittest" have doubtless survived and multiplied, yet natural selection and sexual influences seem scarcely to account for the amazing number of peculiar forms, and their limited distribution even in each of the larger Islands.

If the intact one third of Cuba were submerged not a few species would become extinct, — the same is the case with Jamaica.

The condition of the fauna of S^t. Croix, its relations with that of Puerto Rico, and the great depth of water between them illustrates your views as to the latter being an indication of the time which has elapsed since the Islands were united.

The occurrence of Asiatic forms (Cyclophorus, Diplommatina) in Martinique &^c., and not elsewhere is remarkable,— but the limits of a letter preclude more than a few unsatisfactory remarks. [4]

If, for any reason, you desire to have specimens shewing the diversity of forms prevailing in and characteristic of the faunas of the different groups of the Islands, it will afford me pleasure to supply you.

I may mention that I have been a Fellow of the Geological Society of London for since 1836,⁸ but now for some years non-resident.

You will I am sure excuse my thus trespassing upon you.

I am, Dear Sir, | truly yours | Tho^s. Bland [signature]

Alfred R. Wallace Esq