REPRODUCTION IN THE DOMESTIC FOWL. 1 97 



There was no shell gland or vagina." This bird had a normal 

 ovary and the oviduct functioned as far as it was developed. 

 The eggs were then backed up the duct into the body cavity 

 where they were absorbed. A large number of empty egg mem- 

 branes and 14 eggs in every stage of absorption from a normal 

 fresh membrane-shelled egg to empty egg membranes were found 

 in the body cavity at autopsy. While most of these eggs had 

 apparently been normal, 4 of them were double eggs. In one 

 of the four the enclosed egg was also a double egg. Another 

 one was made up of a concentric series of four enclosed eggs. 

 A brief description of these four eggs is given in the original 



paper. 



DISCUSSION. 



The occurrence of double eggs is not infrequently noted in 

 the agricultural journals. Such eggs have usually been mis- 

 taken for normal or double-yolked eggs until broken for domestic 

 use. The observations on the arrangement of the contents is, 

 therefore, usually not noted. When descriptions of the arrange- 

 ment were attempted they have for the most part agreed with 

 those described above. E. W. Pick (n), however, describes a 

 double egg in which he states that the normal yolk was in the 

 "tapered or smaller end of the egg, while in the 'bell' or larger 

 end there nestled a smaller egg, shell intact." So far as we 

 know in all other cases observed where an egg is enclosed in 

 another egg which contains a yolk the yolk is in the blunt or 

 bell end. The egg described by Mr. Pick was supposed to be 

 "an ordinary double-yolked egg" until "broken for domestic 

 use." Since it is necessary to observe very carefully the arrange- 

 ment of the parts of an egg before they are taken from the shell 

 in order to be sure the positions have not been disturbed it seems 

 possible that in this case the record may not be accurate. In 

 specimens I and 2, however, a common egg membrane enclosed 

 a normal hard-shelled egg and a naked egg composed of a normal 

 yolk surrounded by albumen. These two eggs lay with their 

 long axes parallel. At least in specimen I the evidence is con- 

 vincing that the two eggs passed through the isthmus side by side. 

 If two eggs can come side by side as in these cases it is at least 

 possible to conceive that they may occasionally pass. In such a 



