144 



SCIENCE. 



[Vol. XXI. No. 528 



observer. In spit? of the iiiuoh-lauiled simplicity of metric 

 measures, we find that the " litre " has as many meanings as the 

 "pound," that it is addicted to the reprehensible habit of imper- 

 sonating its fellow-measures, that the virtue of its mother centi- 

 metre is open to grave suspicion, and that its own constancy is 

 no better than it should be. What, then, are we to do? The 

 answer to this question appears to me to be plain enough, and, 

 indeed, constitutes the object I have had in view in originating 

 and pursuing the discussion. The lesson of the litre teaches us 

 the importance of a duly that is too often neglected, namely, the 

 prefixing (or affixing) to every scientific paper, or treatise, a 

 table, or other statement, setting forth the values assigned to the 

 constants employed by the author. If this be done, it matters 

 not one whit whether the values chosen are in accordance with 

 the most rigorous determinations or depart therefrom. If any 

 reader choose to attach different values he can then do so; 

 whereas under the present system of every man being a hidden 

 law unto himself, the perusal of a scientific work is not a process 

 to which the phrase " emoUit mores "can be justly applied. 



Another lesson that we may learn from the litre is the futility 

 of a besetting scientific sin, namely, the Affectation of Accuracy. 

 The owner of that holy and hosannad thing, the " scientific con- 

 science," is apt to deem himself " not as other men" and smiles 

 complacently at the thought that he has expended long years 

 and a fortune in determining, for example, that a cubic inch of 

 water under cei'tain conditions weighs 252.28599 rather than 

 252.38598 grains. And yet the same gentleman will, from his 

 lofty pedestal of phjsics, look down with much pity, if not with 

 absolute contempt, upon the equally conscientious entomologist 

 who (vide JVaifwe, Nov. 17, 1892) uears away a thinking and 

 working lifetime in determining whether a certain insect walks 

 upon more than three legs at once. The results of the most re- 

 fined investigations are but approximations to the truth, after 

 all; and in most cases of scientific work an approximation suffi- 

 ciently close to the truth to serve all practically useful purposes 

 can be arrived at easily and expeditiously. Accuracy, therefore, 

 may often be, in the true sense of the term, excessive, even if 

 intrinsically trustworthy; but when we consider that what ap- 

 pears accurate to one generation is regarded as inaccurate by the 

 next, we must surely deem it but a poor thing to boast of. 

 Take, for example, Mr. Clark's confession that up to September, 

 1891, he "had always assumed the cube decimetre and litre to 

 be identical"; a confession which, coming from so distinguished 

 an authority, is tantamount to a demonstration that most other 

 physicists shared the same erroneous impression, and therefore 

 that the much- vaunted accuracy of modern work in physical 

 science has not existed to the full extent claimed. And yet we 

 all know that the work has been really magnificent and solid, 

 both in its contributions to the world's store of knowledge and 

 in its advancement of the welfare of mankind. This certainly 

 teaches us that reasonable care in scientific measurement is suffi- 

 cient care, and that extreme care is, by the very nature of things, 

 doomed to fail of its object. 



A PRESUMABLY NEW FACT RELATIVE TO THE CEDAR 

 WAXWING (AMPELIS CEDRORUM). WITH REMARKS 

 UPON THE IMPORTANCE OF A THOROUGH KNOWL- 

 EDGE OF FIRST PLUMAGES. 



BY EDWIN M. HASBROTJCK, WASHINGTON, D. C. 



It is considered by every one that the individual waxwing laos- 

 sessing wax tips on both secondaries and rectrices is in the highest 

 development of plumage, while a high development of plumage 

 in any species whatever is usually accorded to the older birds. 



Coues states that, " Specimens apparently mature and full- 

 feathered frequently lack the wax-tips"; that "their normal 

 appearance is unknown," and that " birds in the earliest known 

 plumage may possess one or more." Beyond this little appears 

 to be known. 



In a somewhat extensive series of waxwings in the National 

 Museum, in my own and other collections, appendages on the 

 wings were developed in forty-five, fifteen displayed the orna- 

 ments on both wings and tail, while the remainder, apparently 



adult birds, were entirely unadorned. (It might be well to state 

 that the females as well as the males possess these tips, although 

 less frequentl}', while some specimens examined showed the or- 

 naments on both wings and tail.) Now, the natural conclusion 

 from this would be that those birds possessing wing-tips only 

 were older than those having none at all, while the fifteen on 

 which both wings and tail were adorned were even older and 

 were in the highest perfection of plumage. This is disproved by 

 the fact that four birds of the year still in the striated plumage, 

 taken in August, September, and October, respectively, display 

 very distinct tips on the secondaries ; and if on the secondaries 

 at this early age when older birds possess none at all. why should 

 they not also appear on the tail-feathers? The supposition of 

 older birds only being adorned being disposed of, the question 

 arises. When do these horny appendages appear? and on this I 

 am able to throw considerable light. 



It was in the summer of 1884 that I was spending a month at 

 Port Byron, N. Y , when I ran across a nest of the waxwing, con- 

 taining four young, CTery one of which had the wax tips on tail 

 and wings perfectly developed. These birds were nearly fledged, 

 although unable to fly, and I had good opportunity to obi erve 

 them. Not being interested in collecting birds at that time they 

 were not preserved, a circumstance to be regretted, but the full 

 import of these appendages being developed in nestlings was ap- 

 preciated. 



The following table for the calendar yearshows the conditions 

 of specimens examined. So regularly and so nearly is it com- 

 pletely filled that it is evident that an examination of a larger 

 series would undoubtedly fill the gaps.' 



With this evidence it is apparent that these handsome ornament s 

 are by no means a sign of age, but are. on the contrary, a purely 

 individual development, appearing sometimes in their highest 

 perfection in the nestling, while in an adult they may be entirely 

 absent or barely beginning to appear; or again, appearing a few 

 months after attaining first plumage, to go through a regular 

 course of growth and development. Inasmuch as an individual 

 with wax on both tail and wings is exceedingly rare, and the 

 August and September birds are just beginning to acquire the 

 tips it would be interesting to know just how often this develop- 

 ment in the nest occurs, and this is published mainly with the 

 hope of eliciting further information on the subject, and of 

 prompting those in the field to be on the watch the coming 

 season. 



The importance of thus studying the first plumages cannot be 

 too highly estimated, for not until comparatively recent years 

 has a careful and thorough study of the life-history of each and 



1 In this table an attempt has been made to show merely that both sexes 

 are adorned for each month In the respective columns. In a number of In- 

 stances several individuals were found for each. 



