POULTRY DISEASES AND THEIR TREATMENT. 157 



planation of it will make clear the various parts of this organ 

 system. All of the points shown in the figure may easily be 

 demonstrated on a hen, killed during a period of laying activity. 

 It should be noted that this picture is somewhat diagrammatic 

 and not in accord with normal conditions in respect to at least 

 two points. These are : (i) there are two eggs in the upper por- 

 tion of the oviduct. Normally there would be but one there at a 

 time. (2) The proportionate lengths of albumen portion, isth- 

 mus and uterus are not correctly indicated. 



In this figure the various numerals have the following sig- 

 nificance : 



1. The ovary; region in which the ovules (later to become 

 yolks) are still small in size. 



2. An ovule in an intermediate stage of development, larger 

 than those at i, but still not ready to pass into the oviduct to 

 be laid. It is contained in a very vascular capsule, known tech- 

 nically as the follicle. 



3. 3. Ovules still larger and containing more yolk. The low- 

 er one is nearly ready to leave the ovary and pass down the 

 oviduct. 



4. It will be noted that on all the larger follicles there is one 

 region (forming a line) in which there are no blood vessels. 

 This region (4, 4) is known as the stigma. Here the follicle 

 wall breaks and allows the ovule (yolk) to leave the ovary pre- 

 paratory to laying. 



5. An empty follicle in which the stigma has opened and the 

 yolk passed out. 



6. Anterior end of the margin of the funnel (or infundibu- 

 liim) of the oviduct or egg-tube. When an ovule is about to be 

 discharged from the ovary these funnel lips or margins wrap 

 around that portion of the ovary, so that the ovule may certainly 

 pass into the oviduct and not into the abdominal cavity. 



7. Opening of the funnel. Through this opening the yolk 

 passes into the oviduct. 



8. A yolk which has just passed through the funnel opening 

 into the upper portion of the oviduct. 



9. 9. Albumen secreting portion of the oviduct in which the 

 greater portion of the albumen or white of the egg, is secreted 

 by glands in the walls of the oviduct in this region. 



10. First layer of albumen, or white, secreted about the yolk. 



