Nov., 1904.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



273 



of the oscincs. ..." Concerning this fact, \vliich ap- 

 pears to have been first indicated by IJlyth half a 

 century ago, \vc may have more to say on another 

 occasion. Just now we desire to draw especial atten- 

 tion to the plumage of the nestling, which does not 

 appear to have previously occasioned comment. 



There seems to be strong presumptive evidence to 

 show that the primitive coloration of young birds 

 took the form of longitudinal stripes. Nowhere arc 

 these stripes seen to better perfection than in the 

 young of the Kmu. Here, in the very. young bird, we 

 find a long, thin, white stripe extending from the head 

 down the back of the neck, and tailwards along the 

 back on either side of the middle line. Below the 

 trunk-stripe a second occurs, but towards the end of 

 the nestling period it is interesting to notice these 

 stripes appear to increase in number. 'Ihc second, 

 inferior trunk-stripe of the newly-hatched bird now 

 extends forward to join the neck-stripe just described ; 

 and beneath the second, now elongated stripe, a third 

 appears, and this runs upwards to form a second 



Pig. I. — The ncstlinj; of the .Mo<iruk Cas50\\ar>' \Ca^ua>iii.t htii'illi), 

 showing .«;trongl\ marked longitudinal u hite stripes on a dark chestnut 

 background. Only faint tracesof stripes are present on the neck, hut 

 in the Emu they are very conspicuDu.s. 



the tips of the rami of each down feather are pr, duced 

 into long ribbon-like horny processes. But th ,e can 

 be little doubt but that this peculiar structural modi- 

 fication of the down feathers is comparatively recent, 

 since, though these no longer display a pattern, the 

 down feathers of the neck agree precisely with those 

 of the I'-mu, in that they ;ue coloured so as to form 

 very strfingly-marked longilndinal stripes down the 

 back of the neck, while along the Iron! of the neck 

 and the sides of the head these stripes gi\e pla<'e to 

 rows of dots. 



.\pteryx, it may be mentioned, has .1 miifonn grev 

 coloration. 



There is no reason to believe that the Grebes are 

 even remotely related to the Ostriches, yet the nestlings 

 of these birds di.splay a precisely similar style of colora- 

 tion — light longitiiflinal str'ipes on a dark ground 



It is interesting to note that while in the nestling 

 plumage of the " Ratile " birds .and the (irebes we 

 iind a relatively large number of stripes, in all the 

 forms now to be considered the pattern is almost in- 

 \';irial)lv formed bv a metlian and two l.ilcral stripes. 



Fig. 2.— The nestling of the Great Crested Orel>c U'luli'-ii'f: erislalin). 

 The neck stripes are llere strongly marked, as in the Rmu. 



neck-Stripe, running paridlel with the first ; below 

 this third a fourth stripe appears ; this extends from 

 the end of the tibia, upwards and forwards along the 

 flanks, terminating at the base of the neck. The 

 continuous neck-stripe, \f). i, breaks up at the base 

 of the skull into a number of dots in this older bird. 

 In the very early stages the legs bear curious mottled 

 markings, but these rapidly vanish. 



In the young Cassowary (Fig. i), at an age roughly 

 corresponding to the second stage of the Emu, only 

 the faintest traces of spots on the head and neck are 

 traceable. On the trunk we find five white hands 

 sharply defined and set off by a darker ground than in 

 the Emu. The fifth corresponds to the leg and flank 

 stripe of the Emu, but is shorter. 



In the nestling Rhea stripes also occur, but these 

 are less conspicuous and fewer in number than those 

 of the genera just described. The neck-stripes arc 

 obsolete. 



The nestling Ostrich appears to differ from the other 

 " Ratites " in having a uniform coloration. The 

 trunk, it will be remembered, presents a curiously 

 grizzled appearance, and this is due to the fact that 



In some species these stripes are stronj^ly marked, in 

 others barely traceable. 



But great variability in this matter olitains, even 

 among the several species of a single family. In the 

 Tinamous, for example, a medi.an stripe along the back, 

 extending forwards up the neck on to the head, and a 

 dark stripe behind the eye, occurs with some fre- 

 quency. Other of this group are uniformly coloured, 

 or have a dark occipital i^atrh (yol/inciTcits). In 

 Rliyudidlii'i the head and ni-ck are spotted, as in the 

 nestlings of the Ostriches. 



The game-birds are undoubtedly, as a group, striped 

 when nestlings, though in many this striping is giving 

 way to mottling by the breaking up of the stripes. 



The nestling Curassow, e.g., Crax alector, is 

 conspicuously banded. The mid-dorsal line is marked 

 with a broad dark chestnut band, tended on either 

 side by a conspicuous white stripe ; the band com- 

 mencing on the head, and widening backwards. The 

 white bars also commence on the head. Again, in the 

 voung Argus Pheasant we have a similar dark median 

 band bounded by white stripes. In the young Black- 

 cock (Lynirus iclrix) the gener.al ground colour is buff, 



