128 THE entomologist's record. 



repandata and B. cinctaria. The first and last are the most nervous. 

 Again is Mr. Colthrup sure that everything in nature has a use ? 

 What about the vermiform appendix or a pig's tail ? It is probable 

 that everj' natural attribute has had, has now, or will have a utility to 

 its possessor, but whether or not a particular attribute is now at this 

 present time useful, is entirely a question of fact. Mr. Colthrup's 

 argument takes no notice of vestigial organs. Lohophora carpiuata's 

 green bloom may have been useful once, it may merely be an 

 atavistic character (it is found in other members of the genus when 

 fresh) not suflticientlj'^ harmful to be worth eliminating, it may merely 

 be an extraneous chemical condition having no bearing on the survival 

 of the insect, and, moreover, the strong probability is that copulation 

 and oviposition are completed before the green has faded out. L. 

 carpinata does not rest exclusively on birch, and if it did, old birches 

 are nearly always clothed with a pale green lichen, so that the colour 

 would pro tempore be useful. I think fences may be taken into 

 consideration, they are ver}^ like weather broken boughs of trees and 

 dead stumps. 



In Lieut. -Col. Mander's more extended remarks in (1911) Proc. 

 Zool. Soc. Loud., page 696, [which is fittingly followed by Mr. R. J. 

 Pocock's experiments on page 809] ''■'■, I am met by the difficulty that 

 Lieut. -Col. Mander's arguments are tropical and my experience 

 is English, and only a very small part of England at that. Judged 

 alone the position of affairs in Bourbon and jManritius, to which 

 Lieut. -Col. Manders calls attention, seems to present a serious difficulty, 

 but any synaposematic combinations there existing must be brought 

 under the general application of the theories, and the existence of the 

 conditions, apparently inimical to the application unquestionably wovdd 

 no doubt be explicable, were we sufficiently informed, which we are 

 not at present. I cannot pretend to be sufficiently equipped to deal 

 effectively with special cases of this kind, in regard to which I have 

 no first-hand knowledge, but two things struck me. Lieut. -Col. 

 Manders dismisses several of the birds as too small to be possible 

 causes. I believe this to be a fallacy. I do not from my own 

 experience believe that size of insects matters much to a bird if only its 

 beak be strong enough to tear the insect to pieces. Of course a bird 

 with an exceedingly long slender bill, like some Humming-birds, 

 cannot tackle an insect, unless it be a minute one, but subject to that 

 it is very unsafe to draw inferences from relative size. Secondly, 

 absence of material departure from a pattern, figured as little time ago 

 as 1833, not a century, means little when one considers that heredity 

 would tend to keep the species true to type, in the absence of any 

 force tending to cause a departure, and it may well be that this 

 particular synaposematic combination (if such it be) was the product 

 of forces at work long ago, and for such a long time that the facies 

 now existing has become firmly established. It is interesting to note 

 that the Mauritius Kestrel, CercJnieis punctata, seems to have much the 

 same habits as our own bird, and likewise that the remark on the 

 Friviiillidaf not being hunters of insects is contrary to ray experience 

 of the Frini/illidae in England. 



* There is a kind of poetical justice about the juxta-position of these two 

 papers, which, as an ardent advocate of the theories, appeals to me. 



