230 THE ZOOLOGIST. 



parti-coloured mongrel ducks that are now seen in the parks. May we not 

 venture, then, to hope that the authorities of the Crown and the London 

 County Council will turn their attention to this question, and by concerted 

 action wipe out the mongrels without delay. If they will do this, they may 

 rest assured that they will have earned the thanks of the very many who 

 have watched with great appreciation their efforts to make the parks more 

 useful and attractive. — Aubyn Trevor-Battye. 



[All ornithologists must agree with the suggestions of our correspondent. 

 The parti-coloured mongrels, arising from the interbreeding of black, white, 

 and brown varieties of the domestic duck, have neither beauty nor utility 

 to recommend them. They should be cleared away without scruple to 

 give room for the numerous distinct species which will breed truly, or, if 

 hybridising, will give rise to such interesting products as the Bimaculated 

 Duck — a hybrid between the Teal and the Wigeon — and others equal in 

 beauty, some of which are fertile. — Ed.] 



The Wax-like Tips in the Feathers of Ampelis. — I have made 

 the ultimate anatomical structure of feathers a special study for many 

 years during which I have given those of the period before the first 

 moulting special consideration, and have met with some extremely in- 

 teresting things. I have never been so fortunate as to meet with a wax 

 tip while the young bird was still in the nest, but have occasionally 

 seen them in very fresh subjects, or as early as the 25th of July. The 

 development of the appendage, after it has commenced to appear, is very 

 rapid indeed, resembling the process of the growth of the new antlers 

 of a buck. I cannot yet state definitely the length of time, but from 

 three to five days ordinarily, and doubtless sometimes a little more. In 

 a work devoted to the birds of Minnesota, I have made some references 

 to my familiarity with the species, to which I might add many more 

 notes, since that went out of my hands, that are even more in point; but 

 suffice to say, the red wax is secreted in the cilioharaular portion of the 

 barbules of the terminal barbs of the feather. The rapidity of the 

 development of the appendage is such that occasionally it results in doubling 

 the whole series of barbs, with their barbules, back upon the rachis of the 

 feather, and reveals the fact that the horny material constituting the wax- 

 like mass is filled from the tip, shaftward, as if in fact, as in appearance, it 

 cousists of genuine red sealing-wax, which has become so thickened or 

 condensed as to cease flowing before quite reaching the point of union of 

 the barb with the delicate, overladen rachis. The naked portions of those 

 barbs becomes an easy object of observation under low powers of the micro- 

 scope, and under supremely good light and a higher magnification the 

 reflected portions of the barb with its barbules, and even the barbicels, may 

 be seen resting upon the unreflected portion of the barbs and rachis. That 

 there is some special condition, very temporarily involved, that produces 



