274 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Nov., 1904. 



the back of the neck bears a median stripe which 

 bifurcates at the trunk to run down on either side of 

 the middle Hne in the form of two indistinct Hnes. 

 The occiput and the rump are of a warm chestnut 

 colour. But the general effect of this pattern is 

 mottled rather than striped. This mottling is more 

 pronounced in the Capercailzie nestlings, and in those 

 of the Pheasant and Partridge ; probably this mottling 

 is derived from the breaking up of sfri|3es ; the last 

 phase of the striped dress being seen in the nestling 

 Red Grouse. 



The nestling stages of the t'hardriifurmes, or at 

 least the Limicolw and Lari, appear to ha\c been 

 originally striped. To-day these stripes are most ap- 

 parent in the Redshank, Woodcock, and Norfolk 

 Plover {(Edimciiiiis crcpilaiis). In the Redshank we 

 find a narrow median dorsal stripe extending forwards 

 up the neck and bifurcating on the crown of the head. 

 On either side of the median stripe are three lateral 

 stripes — these stripes are dark on a buff ground. In 

 the Woodcock the median stripe takes the form of a 

 broad chestnut band. The lateral stripes are wanting. 



Fig. 3.— The nestling of the Common Sn\ifl2 ytj lUuuign c,ilc^tts\. There is 

 asecond nestling between that in the foreground and the adult. Note 

 how the stripes in the adult harmonize with the ribboo=like leaves 

 of the grass. 



The .Snipe, however (I'ig. 3), is distinctly striped. 

 In dalliHagi) calcsln (the Common .Snipe), lor example, 

 the general colour of the down is of a rich dark chest- 

 nut, relieved by three \erv distinct white stripes. The 

 ;idult is also, it may be remarked, longitudinally 

 striped. The Norfolk Plover has the ground colour 

 of the body of a pale yellov^ish grey, relieved by two 

 narrow black bars or lines along the back, and a black 

 stripe through the wing and down the middle of th.e 

 head. 



In the other Plovers the stripes h.ave broken up to 

 form mottlings as in tin* (lulls. But the general 

 cdloration is obviously adaptive — procryptic. Thus, in 

 the Kncit — which breeds in the snow — the down is 

 white, mottled with grey ; the young Kentish Plover 

 has the upper parts \ cry pale Iniff, powdered with 

 black ; and so on. The under parts, as in the case of 

 nearly all nestlings, are eillier pure white or nearlv so. 

 Tlv |ac;ma bears strongly-<K-llncd narrow black stripes 

 (in .1 bright chestnut groinid. 



i'he Culls, like the Plo\ers, show lioth striped and 

 mottled forms, the former being rare. Indeed, so far, 

 the only striped form I ha\e come across is the nestling 



of the Little Tern. The ground colour in this species 

 is pale relieved by a median and two lateral stripes. 

 From this we pass to the mottled type, and in many 

 cases, e.g., Common Gull, the median and lateral 

 stripes are still plainly visible ; the neck, too, is spotted 

 just as in the young of Droma'us, also indicating the 

 derivation of the spots from stripes. The young 

 Sootv Tern is almost unicoloured, powdered with 

 minute white points ; and from this we pass to the 

 completely unicoloured and dark young of the .Skuas. 

 The Skuas, it is to be noted, are of a uniform dusky 

 colour. 



The Gruiformcs would appear to have been origin- 

 ally striped, inasmuch as traces of a broad medi;in 

 band are visible in the young Japanese Crane, while 

 the young Bustard (Otis tarda) bears a close re- 

 semblance to the young Gull, being pale-coloured with 

 dark mottlings. 



The voung of the Turnices are striped. 

 The nestling Rails at the present day are all dusky 

 in colour, yet the young of the Black-tailed Water- 

 Hen {'Microti-ibpiiyx veniralis) shows distinct traces of 

 a median and two lateral stripes. 



The .Anseriformes, like the Rails, have now typically 

 uniformly coloured nestlings. .As a rule the upper 

 parts are dark, the central light. But the young of 

 the Mallard and its near allies have their upper parts 

 relieved bv light-coloured spots — one over the thigh 

 and one behind the wing. In many Anatidse there is 

 a strongly-marked superciliary streak, and a streak 

 passing from the lores to the eye, and behind this to 

 the base of the skull. These markings appear to be 

 remnants of an earlier striped condition. The Shel- 

 drakes depart from this type, having a broad dark 

 median band which passes upwards along the neck and 

 invests the whole of the upper part of the head. A 

 dark patch behind the wing gives the semblance of a 

 white streak on either side of this median band. In 

 the \'ariegated .Sheldrake (Casrirca raricgata) the dark 

 median band expands over the shoulders to form a 

 transverse band. Whether this peculiar coloration of 

 the downy Sheldrake is a modification of an earlier 

 striped condition or a specialised condition it is not 

 easy to say, but it seems probable that the latter is the 

 case. The under parts, as in all the other Ducks, are 

 white. The downy young of Swans and Geese, and 

 of Chauna display no markings, and are either pale 

 grey, or pale yellow in colour. 



We come now to a number of groups in which the 

 young appear to be invariably uniformly coloured. 

 But, it is to be noted, these young are all nidicolous — 

 born blind and helpless ; and it may well be that these 

 have long since lost the ancestral striping. Many are 

 reared in holes, and in those which lav in open nests 

 the striped pattern of the down would probably afford 

 no protection. 



The Stcganopodes (Gannets, Tropic-birds, Frigate- 

 birds, etc.) ha\c the young clothed in white down. 

 In the Ciconi;e (.Storks) the young may be thickly 

 clothed «ith long white down, or thinlv clad in long 

 thread-like down feathers, e.g., Herons. 



In the Tubinares (Petrels) the down is either white 

 (.Albatross) or dusky (Petrels). In the .Sphcnisci 

 (Penguins) it is dark grey or tawny yellow. In the 

 Colymbi (Divers) dark grey. In the Accipitres it is 

 white or grey. In the Striges and other Coraciiformes 

 the down, when present, is either white or grey in 

 colour. 



Among the birds, as in other vertebrate groups, 

 longitudinal stripes do not necessarily give place to a 



