28 



ring. At the twenty-fifth to forty-eighth week the fetus meas- 

 ures 3 feet; it is completely covered with hair, and the testicles 

 pass into the scrotum. The vaginal ring is very wide, and slight 

 hernia is generally present. 



The embryo of the ox at twenty-eight days has a length of 2-3 

 inch, and corresponds in its development to the sheep embryo 

 of twenty-five days. At six weeks the embrj^o is 4-5 inch in 

 length, and corresponds to the twenty-two-twenty-three days 

 old dog's embryo. At seven weeks it is about 1 1-5 inches in 

 length; the udder begins to form; the kidneys and ureters are 

 present. At eight weeks the embryo is from two inches to 2 3-5 

 inches. At eleven weeks, 4 2-5 inches, and its development cor- 

 responds to that of the horse's embryo of the same age; mouth- 

 groove and nostrils are closed by a thin membrane; the divisions 

 of the stomach are present. At twelve weeks the embryo meas- 

 ures 5 3-5 inches. From the fourteenth to the twenty-second 

 week the embryo increases from 5 3-5 inches to 12 3-5. At 

 eighteen weeks the hair appears and the testicles descend into 

 the scrotum. The embryo at the end of thirty-two weeks meas- 

 ures about 25 inches. From the thirty-third to the fortieth week 

 the fetus measures about 32 inches. 



The embryo of the sheep at eighteen days has a length of 1-3 

 inch. At thirty-two days indications of the feet appear. At 

 twenty-five days it has a length of 2-3 inch; indications of the 

 eyes, ears, and tail are present; the intestine exists as if con- 

 nected with the umbilical vesicle; the AVolfiian body is well 

 developed. At the fifth week the embryo has a length of 1 inch, 

 and in development corresponds to the twenty-five days old dog's 

 embryo. At nine weeks 3 3-5 inches; the nostrils are still closed. 

 At the tenth to eleventh week the embryo of the sheep and goat 

 measures 6 2-5 inches; hair is still wanting. From the thirteenth 

 to the eighteenth week it measures from 10 to 13 inches. At 

 the twenty-first to twenty-second week the fetus has a length of 

 about 18 inches; goat, 13 or 18. 



The pig's embryo at twenty-one days has a length of about 1-3 



