Birds of Celebes’. Cacatuidae. 
131 
fifteen species comprising the genus, as recognised by Count Salvadori, are 
placed by Prof. Reichenow in his Conspectus Psittacorum in two subgenera, 
— the characters of which were first clearly shown by Dr. Sclater in 1864 
(P. Z. S. 1864, 188) — recognisable by possessing a long, recurved crest of 
narrow feathers, or a crest of broadened feathers generally decurved, respectively. 
Each of these subgenera consists of two sections, the characters of which are 
well pointed out by Reichenow. 
Dr. Finsch makes a different division of the genus Cacatua in his key to 
the species, gathering the species into two groups distinguishable by having 1. 
the nostrils and cere naked and the bill black, or 2. the nostrils and cere 
feathered and the bill light. 
To our mind the genus shows itself to be composed of 3 natural groups: 
1. Bill large, black; cere and nostrils naked; crest long, of narrow 
feathers, curving upwards at the extremity: 
C. galerita (Lath.): Australia, Tasmania. 
C. triton (Temm.) : New Guinea and the islands close by; Aru. 
C. citrinocristata (Fraser): Sumba. 
C. pm’vula (Bp.): Timor, Semao, Flores, Sumba wa, Lombok. 
C. sulphurea (Gm.) : Celebes; Buton. 
2. Bill comparatively small, white or horn-colour or yellowish; 
cere and nostrils feathered; crest of short broad feathers, de- 
curved — in one case (C. leadheateri) lengthened and recurved: 
C. sangumea Gld.: N. Australia. 
C. gofjini (Finsch): Timorlaut. 
C. ducorpsi J. & P. : Solomon Is. 
C. gymnopsis Sclat. : Australia. 
C. haematuropygia (P. L. S. Mllll.) : Philippine and Sulu Islands. 
C. roseicapilla Yieill. : Australia. 
C. leadheateri (Vig.): S. Australia. 
3. Bill large, black; cere and nostrils naked; crest of very long 
broadened feathers, more or less decurved: 
C. alba (P. L. S. MiilL): Halmahera Group. 
C. ophthalmica Sclat.: New Britain. 
C. moluccensis (Gm.): Ceram, Amboina. 
To these points it may be added that in C. galerita of Group 1, and in 
C. leadheateri of Group 2, the oil-gland has been found to be present; in C. alba 
of Group 3 it is generally absent, or reduced to a small membranous mamilla 
(Garrod 5, Nitzsch h 3). It is stated by Garrod that the oil-gland has not 
been found in C. sulphurea^ but, according to Nitzsch, it is present. 
It has been stated that Meckel found a right carotid artery of reduced 
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