vol O17 ~ Recent Literature. 97 
Cooke’s ‘Second Annual Report of Bird Counts in the United 
States.’!1— This posthumous work of Prof. Cooke’s is a further report 
upon an investigation which was originated by him and in which he was 
deeply interested. His idea was to obtain as many carefully made counts 
as possible of the number of birds breeding on definite areas of farm land 
and with these as a basis, estimate the actual number of breeding birds 
over much larger areas. No less than 315 counts were received for 1915, 
covering nearly all the States of the Union, but mainly as in 1914, from the 
northeast. A comparison of the reports from this region for the two years, 
we have as the average bird population for each 100 acres of the area cov- 
ered, 119 pairs in 1914 and 125 pairs in 1915. 
Many other interesting facts are demonstrated and while it is too early 
to draw detailed deductions the practicability and importance of this line 
of investigation are clearly shown, and it is to be hoped that the Biological 
Survey will continue the compilation of data on the lines which Prof. 
Cooke laid down.— W. S. 
Pearl and Curtis on Dwarf Eggs.?— In this paper the character and 
cause of ‘runt’ eggs are discussed at great length. It seems that these 
dwarf eggs usually occur but once or twice in the history of one bird, and 
are generally due to some temporary stimulation and are not correlated 
with a morphological disturbance of the sex organs. 
Some dwarf eggs are yolkless while others contain small yolks. While 
the authors’ study has been based entirely upon eggs of the domestic fowl 
their conclusions undoubtedly apply to other birds as well.— W. S. 
Shufeldt’s ‘Osteology of Palswornis, with other Notes on the 
Genus.’ * — In spite of a colored plate and numerous photographic repro- 
ductions of portions of the skeleton, this paper is disappointing, since one 
fails to get a clear idea upon what points the author bases his conclusion 
that Palwornis and its allies “‘ constitute a subfamily ”’ of Psittacide. 
There are detailed descriptions of the skeletal parts, most of which 
“seem to form no exception to the general rule for Psittaci,” ‘“ are as in all 
of the Psittaci examined” etc. In other cases comparisons are made 
with Ara and Amazona and less frequently with Cacatua and Conurus, but 
nowhere is there a comparative table or a summary from which one can 
get the evidence. 
~ The nomenclature used is a little unfortunate for while Amazona is 
rightly used instead of Chrysotis, the present day changes in the names 
1Second Annual Report of Bird Counts in the United States with Discussion of Results. 
By Wells W. Cooke. Bull. 396, U. S. Dept. Agriculture. October 23, 1916. pp. 1-20. 
2 Studies on the Physiology or Reproduction in the Domestic Fowl — XV. Dwarf Eggs. 
By Raymond Pearl and Maynie R. Curtis. Jour. Agr. Research, VI, No. 25. September 
18, 1916. pp. 977-1042, pll. CXII-CXIII. 
2 Osteology of Palaeornis, with Other Notes on the Genus. By R.W. Shufeldt. Trans. 
Royal Soc. of South Africa. Vol. V, pt. 5, June, 1916. pp. 575-591, pll. XX XIX—-XLI. 
