OVULATION AND EGG TRANSPORT 



105 



THE BODY CAVITY EGGS 



In the body cavity of the ovulating female, or in the finger bowl with the excised ovary, 

 there will be seen some recently ovulated eggs. Since these eggs have not passed through 

 the oviduct they will not be surrounded by jelly but will possess only their vitelline mem- 

 branes which were developed while the egg was in its ovarian follicle. With a wide- 

 mouthed pipette remove some of these eggs to Syracuse dishes containing Standard Solu- 

 tion. 



1. Onto a strip of abdominal muscle, previously excised and mounted on Permoplast 

 with the coelomic surface uppermost, place some body cavity eggs and observe under 

 low power magnification. The peritoneal epithelium is highly ciliated in the female 

 and the eggs will be seen to move across the muscle. Movement is in the direction 

 in which the ostium was located in respect to the excised muscle and peritoneum. 

 Eggs remaining within the body cavity may be observed for movement. * 



2. In a Syracuse dish place a 

 small piece of black silk and 

 some Standard Solution. Onto 

 this silk place several eggs 

 from the body cavity. There 

 should be no movement except 

 that due to convection currents 

 in the solution. With the black 

 silk as a background, attempt 

 to remove the vitelline mem- 

 brane with a very sharp (fine) 

 glass needle and then pefiling 

 the membrane off with watch- 

 maker' s forceps. This is a 

 rather difficult operation but 

 less so with these eggs which 

 possess no jelly covering. 

 Proficiency comes with prac- 

 tice. 



3. Pipette at least 100 body cavity 

 eggs directly into a normal 

 sperm suspension; leave for 10 

 minutes; pour off the suspen- 

 sion; and then add Standard 

 Solution or Spring Water. 



Body cavity eggs have not 

 proven fertilizable although in- 

 semination does produce sur- 

 face figures on some of the 

 eggs which strongly resemble 

 amphi-asters, and possibly 

 abortive attempts to cleave. 

 Should any of the jelly-free 

 body cavity eggs show cleav- 

 age, they should be isolated and observed. If it becomes possible to fertilize the body 

 cavity eggs and have them develop normally, without jelly, it will be a boon to experi- 

 iTiental embryology since the artificial removal of jelly often means damage to the egg. 



OVULATING FEMALE FROG 



(16 Hours after pituitary injection) 



* Through the author there is available a 16 mm. silent moving picture showing these processes. 



