Vol. XXXV.] 70 



adults a break in the continuity of the intergradations in 

 the form of the bill, and because of this break the rule was 

 to consider these two forms as generically distinct ; but, if 

 we examined the form and shape of the bill in young or 

 immature specimens of these two genera, they were found 

 to be identical, with no break in the matter of iutergradation. 

 The logical conclusion was, therefore, that these two genera 

 were phylogenetically related, and that we ought to have 

 some method of classification which would represent or 

 emphasise the fact. 



It might be said that subfamily divisions already did this; 

 but, if we took the five or six genera of the larger Caciques 

 or Oropendolas of the same family, we found these to be a 

 very distinct group, strongly differentiated in various ways 

 from the rest of the Icterid?e ; yet it had been held ])y 

 recent systematists, of whom Mr. Ridgway was one, that it 

 was impossible to subdivide this family into subfamilies. 

 A more complete and extended study of immature forms of 

 the whole class of birds would apparently furnish the only 

 means of arriving at a true conception of the relationships 

 and limits of these larger phylogenetically allied groups ot 

 supergenera. That any real progress in this direction was 

 rendered well-nigh hopeless was due to the fact that at 

 present it was only quite sporadically that nestling or 

 immature examples of species were represented in our 

 collections. This was a matter to be earnestly deplored. 



[Dr. Lowe would have gone on to consider the co-relation 

 of colowr ^pattern with geographical or faunal areas,, and also 

 the question of colour-pattern in regard to sex, but it was 

 found impossible to do this owing to the limited time at his 

 disposal.] 



Mr. W. P. Pycraft : 1 am down on the Agenda to- 

 night as opposing Dr. Lowe : I should just like to say that 

 that is not quite an exact statement of my attitude. I am 

 not opposing him ; on the contrary, in the main I agree 

 with him. With that premise I would like to say that, so 

 far as I am concerned, I have been much too busy lately to 



