NESTLING BIRDS AND WHAT THEY TEACH 257 



The nestling stages of the Chardriiformes, or at least the 

 LimicolEe and Lari, appear to have been originally striped. To- 

 day these stripes are most apparent in the Redshank, Wood- 

 cock and Norfolk Plover {CEdicnemus crepitans). In the 

 Redshank we find a narrow median dorsal strips 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. 



The Snipe, on the other hand, is distinctly striped. In 

 Gallinago coelestis (the Common Snipe), for example, the general 

 colour of the down is of a rich dark chestnut, relieved by three 

 very distinct white stripes. The adult is also, it may be re- 

 marked, longitudinally striped. The Norfolk Plover has the 

 ground colour of the body of a pale yellowish-grey, relieved by 

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

 stripe through the wing and down the middle of the head. 



In the other Plovers the stripes have broken up to form 

 mottlings as in the Gulls. But the general coloration is obvi- 

 ously adaptive — ^procryptic. Thus, in the Knot — which breeds 

 in the snow — the down is white, mottled with grey ; the young 

 Kentish Plover has the upper parts very pale buff, powered 

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

 nearly all nestlings, are either pure white or nearly so. The 

 Jacana bears strongly defined narrow black stripes on a bright 

 chestnut ground. 



The Gulls, like the Plovers, show both striped and mottled 

 forms, the former being rare. Indeed, so far, the only striped 

 form I have 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 Dromasus, also indicating the derivation of the 

 spots from stripes. The young Sooty Tern is almost uni- 

 coloured, powered 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 when adult. 

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