174 



THE OOLOGIST 



BOOKS RECEIVED 



"Check List of the Birds of Illinois, 

 together with a Short List of Two 

 Hundred Commoner Birds, and Allen's 

 Key to Bird's Nests." Illinois Audu- 

 bon Society 1922. 



This valuable little volume of eighty 

 pages was prepared by Benj. T. Gault, 

 than whom no better could have been 

 selected for this particular work. It 

 contains a faunal map of the State, 

 Preface, Foreword of the compiler — 

 List of two hundred commoner birds 

 of lUonois, arranged according to 

 families . Key to Bird's Nests, by Dr. 

 Arthur A. Allen, of Ithaca, N. Y. In- 

 troduction to Comprehensive List and 

 Families, and that List containing 

 three hundred and ninety-three va- 

 rities, with short notes as to most of 

 them and somewhat extended notes as 

 to a number of varieties. It is a 

 credit to the association. 



— R. M. Barnes. 



In American Forestry, Volume 28, 

 page 617, October 1922, appears an ar- 

 ticle by Dr. R. W. Shufeldt, on "Wild 

 Pigeons and Doves" illustrated by 

 thirteen half-tone plates from photos 

 made by the author. This is fully up 

 to Dr. Shufeldt' s usual high standard 

 and reviews these two families of 

 North American Birds in full. 



"The Woodpecker" is the title of an- 

 other splendid paper by Dr. R. W. 

 Shufeldt in American Forestry, for No- 

 vember 1922, pages 584-603. It is popu- 

 lar in style, and illustrated by thir- 

 teen half tones, some from photo- 

 graphs of living specimens, mounted 

 specimens and drawings by the author. 

 It is fully up to the Shufeldt standard, 

 which is mighty close to perfection. 

 American Forestry is to be congratu- 

 lated in having such a contributor. 



R. M. B. 



TWO CRETACEOUS BIRDS 



Ichthyornis and Hesperornis 



In a previous article was described 

 the first bird, Archaeoperyx, which 

 lived during Jurassic times approxi- 

 mately 195,000,000 years ago. 100,000,- 

 000 years later the next birds of which 

 we have fossil record appeared, and 

 our ideas of intermediate types are 

 necessarily based upon interpretations 

 of the evolutional development of 

 Archaeopteryx toward the later forms. 



In Cretaceous times birds reappear 

 in comparative profusion, as speci- 

 mens from Kansas, North Dakota, 

 Montana, New Jersey, and England 

 have been obtained. During this 

 hiatus their habitat had changed from 

 land to sea for all of the known Cre- 

 taceous species are aquatic. The 

 vertebrated tail had almost vanished, 

 the tail feathers had assumed a fan- 

 like arrangement, the claw-like fingers 

 had become united, and in some forms 

 the wings had almost vanished. The 

 Cretaceous birds retain several of the 

 reptilian characteristics which Arche- 

 opteryx possessed. The bones of the 

 skull instead of becoming fused early 

 as in modern forms, remained dis- 

 tinct throughout life, and the teeth 

 had not yet been lost. It is not strange 

 that the presence of teeth in the 

 earlier of the specimens to be found 

 should at first have remained un- 

 noticed, especially since they were 

 very small. It did not occur to those 

 who first examined them that birds 

 could be provided with teeth, and it 

 was some time before they were recog- 

 nized. 



It is hoped that the great gap in 

 avarian history will eventually be 

 filled, but bird fossils in comparison 

 with those of other groups of organ- 

 isms are very rare. The record is 

 somewhere in the rocks, and lucky, in- 

 deed, will be the paleontologist who 

 unearths it. 



