were taken by Mr. F. Pickard-Cambridge at Dungeness. They were found amongst the shingle on the beach, and also upon a Hedgehog.
3. Hyalomma affine, Neum.—A specimen (a gravid female) of this species was sent for determination to the British Museum in May, 1898, by Mr. P.C. Essex, who picked it up at Feltham. The specimen is very much larger than the ordinary British Tick, and closely resembles the so-called "Camel-Tick" of Egypt and India. My suspicion that it actually was an example of this species that had interested Mr. Essex was partially confirmed at the time by my inquiry eliciting the information that a travelling menagerie had passed through Feltham a short while before. Subsequent examination of the specimen, however, has shown that it is referable to H. affine, Neumann, a species which its describer mentions as common on Tortoises (Testudo græca and mauritanica), and records as taken in England off one of these reptiles. Hence there is no reason to doubt that the Feltham specimen was introduced, and is not a descendant of British-born parents.—R.I. Pocock (Nat. Hist. Museum, South Kensington).
ORGANIC EVOLUTION.
In the last copy of 'The Zoologist' which has come to hand in this out-of-the-way part of the world (Mashonaland), I find that Mr. Distant has terminated his series of deeply interesting articles on "Biological Suggestions," relating to "Assimilative Colouration and Mimicry." In these articles he has brought together a most valuable collection of observations and remarks, made by all sorts and conditions of men, upon the fascinating problems of animal colouration, a collection which bears eloquent testimony to the wide and careful reading of the author; indeed, although it may appear ungrateful to say so, the material offered for the contemplation of the reader is almost bewilderingly profuse—so much so, in my opinion, as frequently to obscure the real aim and object of the essays under a mass of citations. Thus, although many of the points raised by Mr. Distant appeared to be open to discussion, it seemed advisable to see the articles as a whole before attempting to comment on the conclusions which he suggests should be drawn from the records therein brought forward. I deal only with his remarks on "Assimilative Colouration," published in Sept. and Nov. 1898 (Zool. ser. iv. vol. ii. pp. 377 and 453).
If I have rightly comprehended Mr. Distant's meaning, his general object is to show that the theory of natural selection has been pushed too far by some of its supporters in their endeavour to explain colouring in nature, and to this end he propounds two suggestions: primarily, that "in the long past animals were uniformly and assimilatively coloured in connection with their principal surroundings" (l.c., p. 461); and, secondarily, that "it is at least probable that, where we have protective resemblance in a unicolourous
