26 BIRDS OF NEW ZEALAND. 



feather-tracts Those birds which exhibit no spaces have the wings 



rudimentary and useless for the purpose of flight." The Apteryx corre- 

 sponds to the above dictum in Nitzsch's ' Pterylography.' He further 

 remarks (p. 17), "The causes of the interrupted plumage" are "the 

 weight of the feathers and the bending and movements of the limbs and 

 neck." 



In the illustration, feathers of the Spotted Emu of Western Australia 

 (^Dromceus irroratus, Bartlett) and Casuarius westermanni (the unique speci- 

 men of which was named by Dr. Sclater after the distinguished Director of 

 the Zoological Gardens at Amsterdam) are given, to show their bifid 

 character, which does not appear in the family of the Apterygidee ; they have 

 no accessory plume to their feathers. There is a beautiful portrait of 

 DromcBiis irroratus (Trans. Zool. Soc. vol. iv. pi. Ixxvi.) in Dr. Sclater's 

 article on the Struthious birds in the Gardens of the Society ; and he says : — 

 " The feathers of D. irroratus are barred alternately Avith silky white and 

 darkish grey throughout their length, terminating in a black tip margined 

 posteriorly with rufous. Those of D. novce- ho Handles are uniformly blackish 

 grey from the base to the extremity, which is black with a broad sub- 

 terminal band of rufous." This Emu was first described by Mr. Bartlett 

 in 1859. 



Casuarius westermanni, Sclater, is figured under the name of C. kaupi 

 (Proc. Zool. Soc. 1872, p. 147, pi. ix.), and is again mentioned (1874, p. 247). 

 Mr. Keulemans has well given the terminal spot in the feather of D. irroratus. 

 Professor Huxley makes the genus Apteryx represent the fifth division of the 

 Ratitse (Proc. Zool. Soc. 1867, p. 423). He states that " the feathers 

 are without any after-shaft, while in Casuarius and Droniceus " they are " as 

 long as the principal shafts." 



Mr. W. S. Dallas, in the Proc. Zool. Soc. 1865, p. 267, on the feathers of 

 Dinornis, writes : — " The accessory shaft is of a pale horn-colour, and appears 

 to be nearly cylindrical. The structure of the web is somewhat different 

 from that which occurs in the Emu and the Cassowary." This refers to 



