THE Zoo.ocist—NovemseEr, 1875. 4685 
other peculiarities, the modifications in their structure which we 
observe now being partly genetive, partly adaptive. 
Thus this curious phenomenon in the geographical distribution 
of animals can be explained by either of those two theories, and 
does not appear to me to strengthen the position of one more than 
that of the other. The multiplicity of the races which I have 
pointed out above I need not further discuss. As regards the 
Galapagos, this fact is quite in accordance with what has been 
long recognized in the distribution of the birds of the same archi- 
pelago, and the co-existence of several races in Mauritius is 
perfectly analogous to the variety of species of Dinornis in New 
Zealand. 
Descriptive List of the Cassowaries. 
By P. L. Scrater, Esq. 
[Mr. Sclater, the talented Secretary of the Zoological Society, is rendering 
good and great service to the Science of Zoology by publishing, in ‘ Nature,’ 
these little monographs of new and little-known genera, and in no depart- 
ment of the Science was this more required than in the Struthionidous 
birds. We all recollect the time when there was only one species of 
cassowary recognised by ornithologists; but the later researches of natu- 
ralists have increased the number to nine, six of which are actually 
represented by living specimens in the Zoological Gardens. In order to 
render his descriptions more methodical, Mr. Sclater has divided them into 
three sections, giving the following sectional characters, which, however, 
I cannot but consider unnecessary.—Hdward Newman.] 
TABLE OF SPECIES OF THE GENUS CASUARIUS. 
a. Casside lateraliter compressa: appendicula cervicis aut duplici aut divisa, 
1. C. galeatus, ex ins. Ceram. 
2. C. Beccarii, ex ins. Aroensi Wokan. 
3. C. australis, ex Australia bor. 
4. C. bicarunculatus, ex ins. Aroensibus. 
b. Casside transversim compressa; appendicula cervicis unica, 
5. C. uniappendiculatus, ex Papua. 
c. Casside transversim compressa; appendicula cervicis nulla. 
6. C. papuanus, ex Papua boreali. 
7. C. Westermanni, ex ins. Papuana Jobie (?). 
8. C. picticollis, ex Papua meridionali. 
9. C. Bennetti, ex Nov. Britann. 
SECOND SERIES—VOL, xX. 3H 
