1026 Journal of Agricultural Research vol. vi, no. 25 



Case 23 had been laying normally. The dwarf egg was the third egg 

 in a clutch. This egg contained a peculiar nucleus. It appeared to be a 

 yolk membrane constricted in the middle. One half of this membrane 

 was filled with yolk and the other half with a clear liquid resembling thin 

 albumen. The bird was killed a few hours after this egg had been pro- 

 duced. The sex organs were in normal active condition. There was no 

 yolk in the body cavity. Evidently the abnormal yolk was extruded 

 from a follicle which presented no abnormal appearance after the yolk 

 was ovulated. Since this yolk was much smaller than a normal yolk, it 

 is probable that it was formed in one of the smaller follicles. 



Case 29 was killed by the other birds. She had laid a dwarf egg four 

 months earlier and had continued to lay until six days before death. At 

 autopsy a membrane-covered dwarf egg was found in the body cavity. 

 It contained a small amount of very light-colored yolk. The albumen 

 was greenish. The largest empty follicle on the ovary was not more than 

 5 mm. in diameter. There were a few shiny granules on the peritoneal 

 surface which appeared to be remnants of absorbing yolk. Apparently 

 the dwarf egg had remained in the oviduct or body cavity for several 

 days, as the yolk it contained must have come from a follicle which was 

 nearly absorbed. In this case also a part of a yolk seems to have been 

 the stimulus which initiated the formation of the dwarf egg, while the 

 rest of the yolk was absorbed from the body cavity. 



Case 25 was a bird which had been presented by Dr. Edith M. Patch 

 to the Maine Agricultural Experiment Station for dissection. This 

 bird was kept at the Station plant for a few weeks. During this time 

 she laid several normal eggs, but her trap-nest record was not kept. 

 When she was killed for dissection, her sex organs were in a normal 

 active condition. The ovary had a regular series of enlarging yolks and 

 four empty follicles, two of which were nearly full size. The isthmus 

 of the oviduct contained a normal membrane-shelled egg. A small 

 dwarf egg was found in the shell gland. This egg contained coagulated 

 fibers of albumen which resembled untwisted chalazse. There was 

 no yolk or nucleus other than the coagulation fibers. No yolk was 

 found in the body cavity. If in this case the small egg had been ini- 

 tiated by a yolk which was returned to the body cavity and absorbed, 

 the small egg must have been in the duct long enough for the absorp- 

 tion to have been completed. The size of the follicles on the ovary 

 made this seem improbable. The origin of the chalaza-like bunch of 

 coagulation fibers is not known. It seemed probable that these were 

 the efficient initiating stimulus which started the secretion of the rest 

 of the egg. 



Case 26 died from some unknown cause. In the shell gland a dwarf 

 egg was found. This egg contained as a nucleus a small lump of har- 

 dened secretion the size of a pinhead. The sex organs were in a normal 



