10 BULLETIN 51, IT. S. DEPARTMENT OF AGEICULTUEE. 



monly either above or below the normal meridian position. (See 

 PL II.) The -white is frequently thin, and many times rough 

 handling^ combined with other age-accentuating conditions, have so 

 separated the membrane lining the shell from the membrane inclos- 

 ing the egg proper that the form and position of the air space can 

 change as the egg is turned. This aj^pearance has caused the trade 

 term " weak eggs " or "watery eggs." But because these terms are 

 loosely used and have several meanings in different sections of the 

 country, or among different candlers, such conditions are charac- 

 terized in this report as "movable air cells," this term actually de- 

 scribing the change which has occurred. 



In the late summer and autumn, when the lay has fallen off and 

 (he country merchants are withholding stocks for coming high 

 prices, such eggs form a very large proportion of the current receipts 

 of the cities and are, of necessity, used by all of the community 

 who depend upon such sources for their egg supply. 



T\Tien warm weather prevails many of these stale eggs show what 

 is termed " heat " ; that is, the yolk rises in the shell and is flattened, 

 the white becomes thinner than normal, and the air space increases 

 in size. These changes, well shown in Plate II, take place in 

 fertile and infertile eggs, both of which become distinctly stale if 

 kept sufficiently long. In tlie fertile egg, however, there comes a 

 second series of changes, namely, incubation, which, in the very 

 earliest stages after the egg is laid, can not be distinguished by the 

 candling method, but has as one of its accompaniments the rising of 

 the 5^olk to the upper part of the shell. When the shell of a "heated "" 

 egg is broken the germinal spot, if fertile, is seen to be slightly 

 thickened. In an infertile egg the germinal spot is seen with diffi- 

 culty. Such eggs, whether fertile or infertile, are good in appear- 

 ance, odor, and taste, but deterioration is rapid and they will ?iot 

 stand long hauls to market nor keep well in cold storage. Hence, 

 such eggs are used in the egg-breaking plants. Their bacterial con- 

 tent is shown in Table 4, where it will be seen that the bacteria are 

 either very few or entirely absent, and that, bacterially, at least, 

 these eggs are not to be distinguished from eggs just laid. 



