RECORDS OF MEETI^'GS 447 



W. K. Gregory, Present Status of the Problem of the Origin of 



Birds. 

 T. Barbour, Some Remarks upon Matthew's '^Climate and 



Evolution/* (Presented by Dr. W. D. Matthew.) 



Dr. Chapman described the American Museum expeditions to the 

 Andes, which had been in progress for several years. He described the 

 avian zonal faunas of the Western, Central and Eastern Andes and of 

 the high plateaux and valleys between them and their relations to for- 

 ested and arid regions. He endeavored to picture the effects of the 

 gradual uplift of the Andean region upon the original avi-fauna, and 

 showed how this uplift had opened new lines of extension and migration 

 to certain north temperate and ,south temperate bird types. 



Dr. Chapman^s paper was discussed by Dr. Matthew and Mr. Murphy. 



Mr. Beebe said in abstract: The evolution from the wing of ArchcB- 

 opteryx to that of the modern bird is comparatively simple. But the 

 transition of the first lizard which, iguana-like, hurled its flattened, 

 stretched body through the air, to an excellently winged creature like 

 Archceopteryx has not been explained. The more evident feather zones 

 of Archceopteryx — ^the wings and tail — would not account for success in 

 the early stages of scaling, as there would be no adequate support for the 

 hinder portion of the body, such as exists in the pelvic and lateral mem- 

 branes of flying squirrels and lemurs and in the pelvic fins of flying fishes. 



A four-day-old squab of a white-winged dove in the scanty down 

 plumage typical of these birds showed three distinct zones of contour 

 feathers, those of the wings and tail, and a line of twelve flight-like quills 

 across the outer leg and femoral membrane, there being in addition six 

 well-developed coverts above the most exposed flights. This was found 

 to be a character common to all domestic pigeons, as well as to jacanas 

 and owls. The lateness of the season prohibited observation on the nest- 

 lings of other birds. 



It is supposed that this unexpected development of pelvic feathers is 

 an atavistic reminder of the time when creatures living prior to Archce- 

 opteryx were able to scale easily through the air supported by a biplane of 

 feather growth. This tetrapteryx stage finds support in the Berlin speci- 

 men of Archceopteryx, which shows distinct traces of large feathers near 

 the base of the tail and above the tarsal feathering. 



Mr. Beebe^s paper was discussed by Dr. Lucas and Dr. Gregory. 



Dr. Gregory said in abstract : Two opposing views regarding the 

 origin of flight in birds have been developed, mostly since 1900. Accord- 

 ing to the first, advocated by Pycraft, Abel, Beebe and others, the primi- 



