THE COLORATION PROBLEMS. 5 



the Australian, the Indo-Malayan, the African and American sections. 



This forms a basis for considering their birth place and their migra- 

 tions during the geological time illustrated by three maps, showing 

 their present distribution and the probable routes of dispersal in the 

 Triassic and Jurassic periods. The Australian species form the typical 

 genus Xyleutes, these originated in Australia and developed there. To 

 explain the migrations we must accept the ancient Southern Continent 

 of Gondwana, at the beginning of the Secondary period. There were 

 at least three primitive centres of dispersion, Australia, Insulindia and 

 Lemuria. This, with the generic groupings arrived at, show that in 

 reality the Xyleutes have a polyphyletic origin. Their spread was 

 already complete in tertiary times. In this it is difficult to accept 

 literally the statement that the origin of Xyleutinae is polyphyletic, 

 and we doubt if Prof. Houlbert means this, though he says so in so 

 many words, his real meaning we take to be that the ancestors of the 

 family, already Xyleutinae, spread over the Gondwana Continent, and 

 the several groups he recognises developed thereafter, of course 

 separately. 



The essay is founded on a large amount of material in the Oberthiir 

 collection, and shows much thoughtful study. He gives a systematic 

 catalogue of the tribe, showing 72 species. His new genera are largely 

 compounds of Cossus [Melanocossus, Neocossus, etc.), though why Cossus 

 after considering Xyleutes to be nearer Zeuzera than Cossus, is not very 

 clear. 



The Coloration Problem. II. 



By W. PARKINSON CURTIS, F.E.S. 

 {Continued from vol. xxviii., page 246.) 

 The record for 1916 is meagre; this must be explained at once. I 

 had much less opportunity than usual for observation, the institution 

 of summer time having tlae effect of entirely spoiling my before break- 

 fast outings, we had a number of disastrous fires on our best hunting 

 grounds, due to incendiarism, and we had an opportunity not to be 

 missed of studying the habits of two non-insectivoruus birds under ex- 

 ceptionally favourable circumstances, the record, however, carried up 

 to September 30th, 1916. In some cases below I have set out the 

 times of the visits where I considered they were of importance, in other 

 cases I have condensed the account as much as possible. My reason 

 for giving the details will appear more fully in the arguments which 

 will occupy the third section of my remarks. 



The evidence. 

 The times given are mean solar time in every instance. 



1. Corvus monedula, L. The Jackdaw. 

 CorYus frugilegus, L. The Rook. 



Observer. — W. P. Curtis and Time. — Evening. 



Laura M. Cook. Sex. — ? 



Date. — May 27th and 28th, 1916. Duration. — About one hour. 

 Place.- -Rew Down, Isle of Wight. 

 Food. — Large crowds of birds came up from the rookeries and the 



