83 [Vol, XXXV. 



whole or individually from the latter. The reasonable course 

 is either tlie separation of the Herons into many genera or 

 else the usage of only one genus^ Ardea — the latter course 

 being rejected by every worker. 



Dr. Hartert : I should like to say a few words in answer 

 to Mr. Iredale. I quite agree with Mr. Iredale that his 

 genera are perfectly natural, because they could not be 

 anything else, when he makes them so small — often mono- 

 typic ! In my opinion, however, it would be an unsupport- 

 able burden if we made so many genera as Mr. Iredale 

 wishes to make. With regard to the genera of the Herons 

 I do not separate them by colour alone, and this will be seen 

 when the continuation of my book on the Palgearctic birds 

 appears, and many ornithologists will take my view. The 

 Herons are one of those groups in which widely different 

 types are connected by links in such a way, as Mr. Iredale 

 correctly said, that one might almost call the whole assem- 

 blage -^r<?ea. It is very difficult to work unless one takes 

 this view, or else one makes every good species into another 

 genus; the latter would be perfectly "natural," but it is 

 not the best way to dispose of the question, and in such a 

 ease a medium and compromissory course should be taken. 



Dr. C. B. TiCEHURST : I am afraid, after all the learned 

 remarks we have heard this evening, what I have to say will 

 be very elementary. I see on the agenda *' Coloration as a 

 Factor in Family and Generic Differentiation.^' We have 

 heard much as regards the bearing of colour on generic 

 characters, but not much about colour and family characters ; 

 personally I cannot see that the vast majority of families 

 show any uniformity in colour at all. One has only to look 

 at the Turdidse to see the different colorations and patterns 

 which you find in that one family alone. 



Of genera in which the same colour-patterns or colours 

 run throughout, examples will occur to everybody, such 

 as Gallinago, Di^obates, etc. ; also in many other genera 

 which are composed of few species, as in Caccabis, 

 Sturnus, etc, but this is perhaps what one would expect. 

 In other genera colour and colour-pattern seem to go for 

 absolutely nothing : take, for instance, two species like 



