98 



NATURE 



\May 29, 1879 



quoted to the effect that "in July young starlings pass 

 over Heligoland by hundreds of thousands •without a 

 single old bird 2iCComp^xiym% them," the learned Doctor 

 adding that he " cannot regard this as a fact, but as a 

 more or less probable conjecture." This is a rather bold 

 and unceremonious assertion. As, however. Dr. Weis- 

 mann, with reference to the above, and to the autumnal 

 passage of young birds prior to their parents in general, 

 puts the question "but are these really facts f" admitting 

 that if they were they would " seem to be against the 

 sufficiency of the five senses" — and as in any probable 

 future efforts of the learned gentleman's on the above 

 topic, incontestable facts might prove infinitely more 

 useful than ever so voluminous an amount of nicest con- 

 jecture, I beg to be allowed to contribute some state- 

 ments bearing on the question, which are based on daily 

 observations of mine now extending over a period of 

 more than forty years, and made on Heligoland — than 

 which an observatory more favoured for such purposes 

 the rest of Europe may not afford. 



Personal experience the learned Doctor does not seem 

 to command respecting the migratory movements of birds, 

 otherwise it might be supposed that he would have brought 

 forward the results of his observations either in refuta- 

 tion of mine, or in confirmation of the same, and I can- 

 not help adding that in my humble opinion, the treatment 

 in whatever form of so grand and mysterious a pheno- 

 menon as the migration of birds, should be preceded by a 

 study of the same in nature, if only it were in its simplest 

 outward appearances. Such a proceeding would prevent 

 the continual repetition of certain traditional errors, and 

 of the building thereon of fallacious inferences and 

 hypothetical assumptions. 



But to return to the starlings in question. The learned 

 Doctor maintains that I "could not possibly have in- 

 spected a hundredth part of these 'hundreds of thou- 

 sands ' of starlings flying about." Now, to a Heligo- 

 lander, such a view of the question would, if anything, 

 be most amusing. I fully uphold what I stated : all these 

 birds touching Heligoland are inspected, and I may add 

 that such is done by the most competent judges, who, in 

 fact, think very lightly of distinguishing a young starling 

 passing overhead from an old one. 



When, in my correspondence with Prof. Newton, I 

 drew his attention to the fact of the autumnal movement of 

 yoimg birds taking place from one to two months prior to 

 that of their parents, I purposely referred to a species 

 affording the most easy means for obserrations corrobo- 

 rative of my views, viz., the common starling. This bird 

 is one of the very few species which perform their 

 migratory flights at so moderate an altitude as to permit 

 of the most satisfactory scrutiny of each individual of 

 a whole flock. Besides such a scrutiny is greatly 

 facilitated by the different colour of the old and young 

 birds at the season in question ; the former, on the wing or 

 on the ground, appearing at any distance perfectly black, 

 whilst the latter are of a very light brownish-grey colour, 

 verging underneath on a soiled white ; the entire ap- 

 pearance of both differing to such an extent that if a 

 flight of these birds were passing overhead at a height 

 from fifty to three hundred feet, consisting of even a 

 thousand individuals, it would require but the most 

 cursory glance forthwith to detect a single old bird among 

 the whole number. That such appears so rery incredible 

 to Dr. Weismann only proves how very little practice he 

 can have had in these matters. 



Moreover, a very great proportion of these young star- 

 lings alight for some hours on the upper plateau of the 

 rock, and furnishing, in contradistinction to the old tough 

 birds, a rather dainty dish, they are pursued by the Heli- 

 golanders very eagerly, and shot in great numbers ; the 

 island taxidermist, Aeukeus, for instance, succeeding last 

 summer in bagging eighty-three such young birds at the 

 discharge of his two barrels. This latter incident alone 



may prove what quantities of these birds are captured 

 here during the month of July of each succeeding year, 

 and I repeat, they never contain the slightest admixture 

 of old black specimens. 



The above I suppose will be admitted as sufficiently 

 detnonstrative facts, and will I trust exculpate me from 

 "building far-reaching theoretical inferences," a proceed- 

 ing against which the learned doctor gravely says we 

 must guard. May I be permitted to ask : to whom is 

 this warning given ? for hitherto I was rather given to 

 believe that conjectures, theoretical inferences, and the 

 like generally grow much more luxuriantly beneath the 

 limited light of the study-lamp than in the face of free 

 matter-of-fact nature. 



Here may follow a few data respecting the periods of 

 passage of the old and young starlings as noted down 

 from daily observations, and I leave it to Dr. Weismann 

 to admit the same as the documentary evidence of an 

 "excellent ornithologist," as he so courteously terms 

 me, or perhaps to dismiss them as of undemonstrated 

 validity. 



Sturnus vulgaris. — First week in June, 1878, some 

 solitary old birds of extremely abraded plumage — sup- 

 posed to be individuals that had lost their mates or were 

 otherwise disturbed whilst breeding. 



June 20 and 21, great flights of young birds; 22nd, 

 23rd, and 24th, enormous numbers of young birds ; up to 

 the end of the month thousands of young birds daily. 



July I to 12, from a thousand to ten thousand young 

 birds daily ; i6th, many flights of hundreds ; 25th, great 

 many young birds. 



Then follows a pause of two months during which no 

 starlings whatever were seen, the migratory move being 

 taken up again on September 22, when I find noted 

 down ; — 



Starlings, old birds in fresh plumage, flights of many 

 hundreds. 



October 2 and 7, great many old birds ; 8th, flights of 

 thousands ; 13th, Royston crows and old starlings by tens 

 of thousands ; 14th, crows many thousands, starlings 

 hundreds of thousands; 15th, many; i6th, a few only; 

 20th, tens of thousands ; 28th, great many. 



November 18 and 19, flights from twenty to fifty. 



December 9 to 18, flights from forty to sixty daily. 



Thus I have witnessed the autumnal migration of the 

 old and young starlings during the long series of years 

 above stated. Invariably nothing but young grey birds 

 pass over here (and in a broad front extending to both 

 sides of the island) from the latter part of June to the 

 end of July ; then a pause ensues lasting from six weeks 

 to two months, when during the latter part of September 

 the movement is taken up again by the old birds in fresh 

 black plumage, and continued to the close of November — 

 by straggling parties oftentimes kept up till Christmas. 



These are incontestable facts, however incredible they 

 may appear to Dr. Weismann ; but he may rest assured 

 that not only all the young and old starlings passing 

 over here are "inspected," but the many hundreds of 

 thousands of miscellaneous birds visiting this island have 

 to pass a very critical review in addition. 



I cannot conclude these remarks respecting the ques- 

 tion of young birds preceding during their first migra- 

 tory trip their parents by one or two months, without 

 stating that, so far as my long experience on Heligoland 

 extends, there exists, among the 360 odd species collected 

 here by myself, only one solitary exception to the general 

 rule, \a.,^\i(ic\xzVoo,Cuculus catiorus, of which species the 

 old birds precede iht'ir young by at least four weeks. Of 

 all the rest, the young birds of the summer open the grand 

 autumnal flight, unaccompanied by any old, the very finest 

 old males at the close of the season bringing up the rear. 

 In spring, however, quite the reverse invariably takes place, 

 then the most perfect old males appear first, followed soon 

 by old females, and later by younger birds of less perfect 



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