2? RAYMOND PEARL AND MAYNIE R. CURTIS 
have received nearly their full amount of albumen. It can 
readily be seen that if the oviduct egg happens to be an excep- 
tionally large one, relative to the other eggs of the same bird, it 
may have a slightly greater absolute amount of nitrogen though 
not yet laid, than another relatively or absolutely smaller laid 
egg taken for acontrol. It seems quite clear, in the light of data 
collectedin this laboratory onthe fluctuation in size and proportions 
of the parts of eggs'® that this is the correct explanation of these 
apparent exceptions in the chemical analyses. It will be noted 
that in these four cases it is only the absolute amounts of nitrogen 
(and not the percentages) which furnish exceptions to the rule. 
Supplementary evidence 
There is available evidence of still other sorts to indicate that 
there is a real addition of albumen to the egg after it leaves the 
so-called ‘albumen’ portion of the oviduct. In the first place a 
~ histological study of the oviduct which has been made in this 
laboratory by Dr. Frank M. Surface!’ shows that histologically 
the same kind of glands which are found in the so-called albumen 
portion of the duct, are also found in the isthmus and uterus. 
The differences between the glands of the different regions are 
quantitative not qualitative. 
In removing eggs from the uterus it is frequently found that the 
egg is surrounded by a thin fluid which has evidently been secreted 
and is in process of being taken into the egg by osmosis. A case 
of this sort is described in the following autopsy record. 
Autopsy No. 523. Hen 8088. Killed March 28, 1911 for data 
This hen laid at 9 a.m. and was killed at 4.15 p.m., or 7} hours 
after laying. There was an egg in the uterus. The uterus was 
much larger than the egg. When a cut was made in this organ a 
small amount of clear fluid flowed out. The cut was clamped off 
16 Cf. No. 1 of these ‘Studies,’ loc. cit. supra. 
17 Reported at the Ithaca meeting of the American Society of Zoologists, Eastern 
Branch, December, 1910, but not yet published. 
