654 OLD MAN—OLIGOM YODA 
Pigeons as Didunculus (DoDLET), Goura and Treron; in other 
Cockatoos, in several PARROTS (Chrysotis and Pionus), in Podargus 
(NIGHTJAR), Otis, Argusanus and the Fatitx it is absent. This irregu- 
larity shews that it has not much value as a taxonomic character ; 
but attention to other peculiarities in its form or structure has been 
drawn by Nitzsch and Garrod, and especially to the presence or 
absence of a circlet of feathers surrounding the nipple-like orifice, 
and when that occurs the skin covering the gland is naked, while 
when the circlet is wanting the whole is covered with down inter- 
spersed with stiff feathers. Among the birds to which the last 
condition appliés are the Bucconidx, Caprimulgi (excl. Podargus), 
Cariama, Coraciide, Cuculide, Cypseli, Galbulidx, Leptosomus, Mero- 
pidzx, Momotidx, Steatornis and Trogonidx, while by far the greater 
number of birds possess the tuft. 
Analysis of the secretion of the Oil-gland shews that its com- 
position closely resembles that of the sebaceous product of Mammals ; 
but that it differs from milk through the absence of sugar. Its use 
is probably the anointing of the plumage, and the presence of 
POWDER-DOWNS in Cacatua, Chrysotis and Podargus may possibly 
indicate some correlation between these organs and the oil-gland.1 
OLD MAN, the name in Jamaica for Hyetornis pluvialis, one of 
the Cuckows which is also called Rain-bird, as are others of the 
Family. 
OLD SQUAW and OLD WIFE are two of the many names of 
the Long-tailed Duck, the former necessarily of transatlantic origin. 
OLECRA NON, the proximal end of the ULNA, projecting back- 
ward from and beyond its articulation with the HuUMERUS, being 
practically equivalent to the point of the elbow. It serves as a 
lever during the extension of the wings, the tendons of the triceps 
muscle being inserted on the Olecranon. 
OLIGOMYOD, Prof. Huxley’s name (Proc. Zool. Soc. 1867, 
p. 471) for the group of Passerine Birds having but few song- 
muscles (SYRINX) which Johannes Miiller had previously called 
PICARIL. 
1 Tt seems that it would be improper here to overlook a controversy on this 
still unsettled question which, though now wholly forgotten, was carried on, to 
the amusement of our predecessors, in the later volumes of Loudon’s Magazine 
of Natural History, and in the early years of The Zoologist. Waterton, with 
the mistaken zeal he so frequently exhibited, maintained that the gland had no 
lubricating function, chiefly because he had observed that the so-called ‘‘rump- 
less” breed of Fowls, in which the gland is wanting, kept their feathers as glossy 
as other Fowls which possessed it. He was easily victorious so long as he had to 
deal only with the late Mr. F. O. Morris, but when he met with an adversary 
like the late Mr. C. A. Bury, who knew something about birds, was a good 
observer and could write rationally, Waterton’s mistaken position seems to have 
become plain to him, and he retired from the contest.—A. N. 
