134 T'ransactions.— Zoology. 
spiders’ nests contain a cluster of flesh-coloured eggs, or young, and in tearing 
them off the bird necessarily exposes the contents, which it eagerly devours. 
Thus, while engaged in collecting the necessary building material, it finds also 
a plentiful supply of food—an economy of time and labor very necessary to a 
bird that requires to build a nest fully ten times its own size, and to rear a 
foster-brood of hungry cuckoos in addition to its own” (l.c., p. 42). 
This statement appearing, I suppose, fanciful to Captain Hutton, he 
ventured, in the “ Critical Notes" appended to his Catalogue of New Zealand 
Birds (p. 73), to pronounce these spiders’ webs nothing but fresh-water Alge ! 
Captain Hutton afterwards wrote to me, admitting his error, but I cannot 
find that he has made any avowal of it in his numerous communications to the 
Institute. This omission is, I think, to be regretted; for while it is perfectly well 
understood that the “opinions” of a writer on any question of science are a 
fair subject of criticism and discussion, one naturalist has no right to impugn 
` the accuracy of another in matters of fact, or to throw doubt on his habits of 
observation, unless in doing so he can adduce something better that mere 
conjecture. 
Rattus mopestus, Hutton. 
The October number of “The Ibis” contains a communication from 
Captain Hutton in defence of this species. He combats my judgment in 
referring his type specimen to Rallus diefenbachii, juv. (“Birds of New 
Zealand,” p. 180), and enters upon a long argument to prove that not only 
are they distinct species, but that they belong to different sub-genera. 
Tnasmuch, however, as there is a fatal mistake in Captain Hutton’s premises, 
his conclusions go for nothing. 
distinct species.” Starting, therefore, with the assumption that Rallus 
diffenbachii and R. philippensis are the same—in which he is entirely wrong— 
he proceeds to prove that Rallus modestus “ belongs to a different sub-genus 
from Rallus philippensis.” He gives a figure to show that “the bill of 
Е. modestus is much more slender and longer in proportion to the size of the 
bird than in R. philippensis,” and indicates other points of difference. x 
Granting the whole of his argument as regards Rallus philippensis, that is 
quite beside the question of Rallus modestus and R. dieffenbachii being the 
same, which is the only point in issue. 
Let the reader glance at the subjoined figures (by Keulemans) of the heads 
