Dear & much respected Sir

Adding to the answer of your letter from Dec. 13¹ my best thanks for the highly interesting memoir, in the meantime arrived, on Lythrum,² I must begin with lamenting that I have not been able till today to promote very much the proposed monograph about wild oxen,³ to which you have so largely contributed by sending me one of the most interesting types.⁴ Yes the Plates destined to that memoir are all finished since long and also a great deal of Wood-engravings and the text for the european Species. But having perhaps inconsiderately extended my purpose over the Linnean Genus Bos in general, I have much been arrested by the necessity of seeking the materials for foreign species in the different museums of the continent, and also by the unevitable consequence to compare the fossil species. Nevertheless I am as much at the work as the many incumbent other obligations permit,⁵ so that I hope, that before the end of the year we just began, the labour will be done.

As to the skull from Lord Tankerville, I received from you, it is indubitable, that it is the purest descendant known of the fossil Bos primigenius, be it a remnant of the extinct wild race, as I presume, or a flock grown wild (Verwildert) of a formerly tamed breed;⁶ certainly the flock of Lord Tankerville, the very allied Pembroke-breed and the predominant type in our lake-habitations of the stone age do not differ otherwise from the extinct primigenius than by Minor Size; yet the eminent size of the archetype has not seldom been reached by single Individuals in Seedorf, Robenhausen and other Swiss lake localities.⁷

I do not know the white cattle of the King of Sardinia otherwise than by the drawings given by different illustrated papers f. e. in the Field (the Country Gentlemans News Paper) Jan. 10. 1863 and elsewhere. It is a tamed type not rarely kept in Umbria, but, as Prof. D. Filippi at Turin writes me, especially bred in Val di Chiana near Arezzo (the home of the extinct Bos trochoceros.)⁸ Having seen no skull of that type it is difficult to judge about its affinities, but I am very much inclined to consider the so said Bos trochoceros as a mere race of Bos primigenius, to which belongs also the long horned cattle of Italy and Hungary; it seems very probable therefore, that the breed of Val di Chiana has the same origin.⁹

I should be very glad to know, what you think about the conclusions drawn from the facts observed in the milk-dentition of Horses and other animals, and exposed or rather hidden in my paper on fossil horses.¹⁰ I admit willingly, that the tableau or pedigree (page 86) founded on the peculiarities and affinities of the dental system is a premature essay, but I feel convinced, that the considerations exposed in 78–90 can grow fertile, and that the identity of the milk-dentition of certain species with the dentition of the full age of other species historically precursors of the former, contains hints not to be overseen. I think that it is more than an accident, that the dentition of Anoplotherium and Dichobune is preserved to-day in the milk teeth of Moschus and Tragulus, that Merychippus has in the youth the dentition of the miocene Anchitherium, in the full age that of Equus., that the diluvial Equus fossilis inherits in its young age the dentition of the miocene Hippotherium, and the recent Equus Caballus that of the Equus fossilis etc. etc. (pg. 38. 57. 74. etc. 101 etc)¹¹

Whishing Sincerely, that you may soon fully recover from your illness¹² and being, with much pleasure at your disposition as often as I can hope to serve you, | I remain, with much respect, | Dear Sir yours sincerely | L Rütimeyer

Basel 3 January 1865.