DINORNIS— DIVER 151 



Limicolx, as the Dotterel, Godwit, Phalarope, and Rhynchxa or 

 Painted Snipe, as well as in some of the Turnicidse (Hemipode). 

 No single explanation that will iit all these cases seems possible ; 

 but in those of the LimicoliX, just mentioned, it is to be remarked 

 that the females are not only larger but are more conspicuously 

 coloured than the males, which latter are believed to perform 

 exclusively the duty of incubation. In the loAver classes of Ver- 

 tebrates the production of the often numerous eggs may be the 

 original cause of the gi-eater size of the females. 



DINOENIS, see Moa. 



DIPPER, a name now in general use for the Water-OuSEL, 

 but apparently invented in 1804 by the author of Bewick's British 

 Birds (ed. 1, ii. p. 17) because "it may be seen perched on the top 

 of a stone in the midst of the torrent, in a continual dipping motion, 

 or short courtesy often repeated," and not (as commonly is sup- 

 posed) from its habit of entering the water in search of its food. 



DISHWASHER, a common name in many parts of England, 

 especially in the south, by which the Pied Wagtail, Motacilla 

 lugubris, is known ; and given also in Australia to Sisv/ra inquieta 

 (Flycatcher). 



DIVER, a name that when applied to a bird is commonly used 

 in a sense even more vague than that of Loom, several of the Sea- 

 DucKS or Fuligulinse and Mergansers being frequently so called, 

 to say nothing of certain of the Auks or Alcidse and Grebes ; but 

 in English ornithological works the term Diver is generally re- 

 stricted to the Family known as Colymhidse, a very well-marked 

 group of aquatic birds, possessing great, though not exceptional, 

 powers of submergence, and consisting of a single genus Cohjmhus 

 (or Eiidytes of some wiiters) '^ which is composed of three or four 

 species, all confined to the northern hemisphere. This Family 

 belongs to the Cecomorph^e of Prof. Huxley, and is usually sup- 

 posed to occupy a place between the Alcidse and Podicipedidse ; but 

 to which of those gi'oups it is most closely related is at present 

 undecided. Brandt in 1837 (Beitr. Naturgesch. Vogel, pp. 124-132) 

 pointed out the osteological differences of the Grebes and the 

 Divers, urging the affinity of the latter to the Auks ; while, thirty 

 years later, Prof. Alphonse Milne-Edwards (Ois. jfoss. France, i. 

 pp. 279-283) inclined to the opposite view, chiefly relying on the 

 similarity of a peculiar formation of the tibia in the Grebes and 

 Divers,^ which indeed is very remarkable, and, in the latter group, 



1 By these writers the name Colymhus is generally used for what others term 

 Podiceps, more correctly written Podicipes. Americans of late prefer Urinator. 



" The remains of Colymhoides minutus, from the Miocene of Langy, described 

 by this naturalist in the work just cited, seem to shew it to liave been a general- 

 ized form. Unfortunately its tibia is unknown. 



