250 



NATURE 



{July 29, 1875 



somewhat of a vagrant, there is no improbability of her 

 being subject to so much regularity of habit, and 

 indeed such has been asserted as an observed fact. If, 

 then, this be so, there is every probability of her offspring 

 inheriting the same habit, and the daughter of a Cuckoo 

 which always placed her egg in a Reed Wren's or a Tit- 

 lark's nest doing the like." To this Mr. Harting very justly 

 replies — " This would be an excellent argument in sup- 

 port of the theory (of Dr. Baldamus) were it not for one 

 expression, upon which the whole value of the argument 

 seems to me to depend. What is meant by the ex- 

 pression ' Once successfully deposited ? ' Does the 

 Cuckoo ever revisit a nest in which she has placed 

 an egg and satisfy herself that her offspring is hatched 

 and cared for? If not (and I believe such an event 

 is not usual, if indeed it has ever been known to 

 occur), then nothing has been gained by the selection of 

 a Reed Wren's or Titlark's nest (as the case may be), and 

 the Cuckoo can.have no reason for continuing the practice 

 of using the, same kind of nest from one season to 

 another." Mr. Harting therefore rejects the application 

 of this principle in the case of the Cuckoo. We will suggest 

 to him a modification of Prof, Newton's argument which 

 may perhaps lead him to return to it in its modified form. 

 The assumption that the bird which once successfully 

 deposited 'her eggs in a Reed Wren's or Titlark's nest, 

 would again seek for one of the same, species in other 

 seasons because of her sagacity, or her knowledge of its 

 successful hatching, is highly improbable in our estima- 

 mation, and not essential for the subsequent deductions, 

 in a Darwinian point of view. It is more logical to 

 suppose that ancestral Cuckoos deposited their eggs 

 broadcast. That those which got into Reed Wren's and 

 Titlark's nests (as in instances) all, or nearly all, hatched 

 out ; whilst those deposited elsewhere perished. The 

 young inherited those peculiarities of the mother birds 

 whose tendency was towards the utihsation of the Reed 

 Wren's and Titlark's ' nests, and as a result the modern 

 Cuckoo tends to place its eggs in those nests. 



The evidently genuine sketch made by Mrs. Blackburn 

 of the nestling Cuckoo ejecting the young of the Titlark 

 along with which it was hatched, first published in the 

 introduction to Gould's " Birds of Great Britain," is 

 introduced as confirmatory evidence in favour of this, to 

 the foster-brethren, murderous propensity of the young 

 birds, with reference to which so many naturalists are 

 still sceptical. 



The peculiarity in the distribution of the Nightingale 

 in this country is difficult to explain, especially as the 

 Wryneck keeps within nearly the same boundaries. 

 " When we find this bird in summer as far to the west- 

 ward as Spain and Portugal, and as far to the northward 

 as Sweden, we may well be surprised at its absence from 

 Wales, Ireland, and Scotland ; and yet it is the fact that 

 the boundary line, over which it seldom if ever flies, 

 excludes it from Cornwall, West Devon ; part of Somer- 

 set, Gloucester, and Hereford ; the whole of Wales 

 {a fortiori from Ireland), part of Shropshire, the whole of 

 Cheshire, Westmoreland, Cumberland, Durham, and 

 Northumberland." From these data it is not difficult to 

 recognise that with but few exceptions the Nightingale 

 only visits those parts of this country which are, covered 

 with secondary or tertiary geological formations ; and it I 



has always seemed to us that it must be that the primary 

 soils do not produce food suitable for the insects on which 

 it feeds. It is true that the new red sandstone is the soil 

 of Cheshire, and that much of Yorkshire and Derbyshire 

 are primary formations, nevertheless the two boundaries 

 are so similar in other respects that it is hardly possible 

 that there is no relation between them. 



There is another disputed point to which the author 

 more than once alludes. He remarks that " we cannot 

 help thinking that the Nightingale and many other birds 

 which visit us in summer and nest with us, must also 

 nest in what we term their winter-quarters ; otherwise it 

 would be impossible, considering the immense number 

 which are captured on their first arrival, not only in 

 England, but throughout central and southern Europe, to 

 account for the apparently undiminished forces which re- 

 appear in the succeeding spring." The late Mr. Blyth 

 was of an opposite opinion, and further observations are 

 necessary before this question can be settled. 



Besides the information given on subjects like the 

 above, the nest and eggs of all the species, fifty in number, 

 are described ; whilst exact measurements are included 

 of closely allied forms, such as the Wood Warbler, the 

 Willow Warbler, and the Chiff Chaff; the Red Warbler, 

 the March Warbler, &c. Their plumage and nests are 

 also compared in detail. 



To those who reside in the country and are fond of the 

 study of nature, this work by Mr. Harting will be found as 

 useful an addition to their libraries or their drawing-room 

 tables, as it will be to ornithologists generally. 



OUR BOOK SHELF 



Meteorology of West Cornwall and Scilly, 1871 atid 1874. 

 By W. P. Dymond. (Reprinted from the Annual Re- 

 ports of the Royal Cornwall Polytechnic Society, 

 Falmouth.) 



In the latter of these pamphlets Mr, Dymond gives an 

 interesting discussion of the temperature range correc- 

 tions for Falmouth, and an excellent resutne' of the sea- 

 temperature observations made at the same place during 

 the three years 1872-73-74, which have been made with 

 a just apprehension of the precautions which require to 

 be taken, if observations of sea temperature are to have 

 real scientific value. The omission of tables of daily 

 maximum and minimum atmospheric pressure, which 

 were given in the earlier issue, is a decided improvement ; 

 not so, however, is the omission of the table of the 

 amounts of the rainfall, with the different winds, N., 

 N.E., E., &c., which supply information of great value 

 in defining local climates. 



The five stations reported on are Scilly, Helston, Fal- 

 mouth, Truro, and Bodmin, ofwhich the most northern, as 

 well as most elevated, is Bodmin. If we compare the mean 

 temperatures of the stations for 1874, it is seen that at 

 Bodmin the mean was S3°'3, and at Falmouth only 5i°-8. 

 In some of the months the discrepancy is still greater. 

 Thus the mean temperature of Bodmin is about four 

 degrees higher than that of Falmouth in each of the 

 months from April to July inclusive, and about two 

 degrees higher than at Truro, Helston, or Scilly. It is 

 unnecessary to remark that these differences do not 

 represent the differences of the climates of these places, ' 

 but are to a very large extent only due to the incomparable 

 modes of observation and of reduction of the observa- 

 tions adopted for the several stations. Thus, as regards 

 the exposure of the thermometers, at Bodmin they are 

 hung four-and-a-half feet above the ground, under a thatch 



