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Science, No. 1, pp. 32–33, and No. 4, pp. 231–2–3, published in the present year,—it will, I think, be admitted that Mr. Jeffreys can hardly claim originality in his statement.

But to prove that Mr. Jeffreys was well acquainted with my previously published observations on the subject, I invite attention to two distinct statements of his which appeared in his Reports on Dredging, and were published in the Annals and Magazine of Natural History, on the respective dates given below:—

It thus becomes manifest that Mr. Jeffreys had studied my writings, but that the opinions entertained by him in 1866 became revoked in 1868; whilst those held by him in 1868 were in turn superseded by views formed and published in 1869! This circumstance is the more significant, inasmuch as Dr. Carpenter, in his "Official Report on Dredging," for 1868 (p. 181), actually singles out the opinion published by Mr. Jeffreys, as above, in the autumn of the same year, as an authoritative illustration of the want of credence which my discoveries had met with!

With regard to Mr. Jeffreys' new division of oceanic animals into zoophagous and sarcophagous, I have nothing to urge beyond my avowed inability to discern any physiological difference between creatures that are zoophagous and those that are sarcophagous. It only remains for me to express my belief that, up to the present period, I have stood alone in maintaining, against Ehrenberg and others, that plant-life, even of the lowest types, becomes extinct at depths exceeding four or five hundred fathoms and in endeavouring, by a series of observed facts, to prove that the nutrition of the Foraminifera and certain other oceanic Rhizopods is effected by a special vital process, which enables them to eliminate and apply to the formation and sustenance of their body and shell-substance, through their surfaces only, the materials which exist in the medium in which they reside.

As I see Professor Newton has, in his very interesting paper on Dr. Baldamus' theory of the colour of Cuckoo's eggs, noticed my "stigmatising" the Doctor's theory as "wild," in my "Birds of Somerset," will you be kind enough to allow me space for a few lines on the subject? Although it is with great diffidence that I venture to differ from Professor Newton, I still cannot help considering Dr. Baldamus' theory as "wild," not perhaps as it appears under the manipulation of Professor Newton, for he seems to me to have pruned and pared it down so nicely that there is but little of the original left; and I think he would not much differ from me in my opinion as to the wildness of the theory, if he had to accept all the allegations in Dr. Baldamus' paper published in Naumannia.^[1] For instance, compare the following passage in Professor Newton's paper in No. III. of Nature with some passages from Dr. Baldamus' paper "Having said thus much, and believing as I do the Doctor to be partly justified in the carefully-worded enunciation of what he calls 'a law of nature,' I must now declare that it is only 'approximately,' and by no means universally true, that the Cuckow's egg is coloured like those of the victims of her imposition. Increase as we may by renewed observations the number of cases which bear in favour of his theory, yet, as almost every bird's-nesting boy knows, the instances in which we cannot, even by dint of straining our fancy, see resemblances where none exist, are still so numerous as to preclude me from believing in the generality of the practice imputed to the Cuckow. In proof of this I have only to mention the many eggs of that bird which are yearly found in nests of the Hedge-Sparrow in this country, without ever bearing the faintest similarity to its well-known green-blue eggs. One may grant that an ordinary English Cuckow's egg will pass well enough, in the eyes of the dupe, for that of a Titlark, a Pied Wagtail, or a Reed Wren, which according to my experience are the most common foster-parents of the Cuckow in this country; and indeed one may say, perhaps, that such an egg is a compromise between the three, or a resultant, perhaps, of the three opposing forces; but any likeness between the Hedge-Sparrow's egg and the Cuckow's so often found alongside of it, or in its place, is not to be traced by the most fertile imagination. We must keep, therefore, strictly to the letter of the law laid down by Dr. Baldamus, and the practice imputed to the Cuckow is not universally, but only approximately true." This certainly is very different from Dr. Baldamus' own statement:—"If Mr. Braune, the forester of Griezland, had not cut this large Willow Wren's (Shippolais) egg (as it seems) out of the ovary of the Cuckoo, which was killed as she was flying out of the Willow Wren's nest; if Count Rödern, of Breslau, was not a reliable authority that this apparent Redstart's egg was taken out of the nest of the Redstart (Ruticilla phoenicurus) had not taken this large Tree Pipit's egg out of the nest of a Tree Pipit (Anthus arboreus); if I myself had not taken out of the nests of the Red-backed Shrike (Lanius collurio) this reddish and this green-greyish peculiarly marked Cuckoo's egg, one might indeed entertain doubts whether this variously-coloured collection—these green eggs, with and without markings; these on white, grey, green, greenish, brownish, yellowish, reddish, and brown-reddish ground; these grey, green, olive green, ash grey, yellow brown, yellow red, wine red, brown red, dark brown and black; these spotted, streaked, speckled, grained and marbled eggs could one and all be the eggs of our Cuckoo! And yet this is indeed the fact!" How different this from the much more cautious and limited statement of Professor Newton, first quoted, which would entirely sweep away some of these varieties, especially those resembling the eggs of the Redstart or the Hedge-Sparrow, for the eggs of these two species do not differ much from each other, and what might be said of the eggs of the one would apply equally to those of the other; yet these are two of Dr. Baldamus' selected species, for, a little further on, he gives a list of the various species from the nests of which Cuckoo's eggs have been taken resembling those of the foster-parent. Of the eggs of the Redstart he says:—"These four specimens, which were found in the nests of Ruticella phoenicurus, are all of a light-green ground colour; two of them have the larger and more or less brownish spots, which on one of them form a zone; the third has similar markings, but only sparingly scattered over the whole surface, whilst the fourth is without any marking at all—herein it is identical with one in the possession of Dr. Dehne, which is uniformly light-greenish blue, without any markings whatsoever."

Of the single specimen of the egg resembling that of the Hedge-Sparrow, No. 15 in his list, he says:—"One of the most interesting of the Cuckoo's eggs is a beautiful blue-green one, which was taken out of the nest of Accentor modularis, without any markings, and which even to the shell, the grain, and the size (bis auf Shale, Korn, und Grösse) is like a very dark egg of the Hedge-Sparrow." On reading this quotation from the statement of the facts on which his theory is founded by Dr. Baldamus in the paper in Naumannia, and comparing it with Professor Newton's paper above quoted, we cannot help seeing that there is a decided issue of fact between them, especially as to the eggs of Accentor modularis.

The conclusion which Dr. Baldamus draws from the facts stated by him is that Nature, by means of such arrangements, has ensured and facilitated the preservation of a species otherwise much exposed to danger, and that she has attained this object by investing every hen Cuckoo with the faculty of laying eggs coloured exactly like the eggs of the bird of whose nest she prefers to make use, according to the locality. Now if this were really the case, and it were really true that this colouring of the eggs were essential for the preservation of the species, would it not be just one of those laws of Nature which we should expect to find universal, or so nearly so that there would be but very few exceptions? But according to Dr. Baldamus himself the exceptions are numerous, and Professor Newton would make them still more numerous, and would no doubt be quite right in doing so. How, then, do the eggs in the exceptional cases prosper? Does the Hedge-Sparrow or the Redstart throw the egg of the Cuckoo out of its nest because it does not resemble its own? or do the birds to whose tender mercies the Cuckoo, according to Dr. Baldamus himself, is occasionally obliged to entrust its eggs when it cannot find a fitting nest in to place them, do so? This does not appear to be at all