564 EMBRYOLOGY. 



(a.) Horse. The embryo grows about one inch weekly, and 

 at the end of the period has a length of about 27 inches. The 

 hair appears on the crest and back. The testicles lie near the 

 abdominal ring. 



(6.) Ox. The embryo at the end of 32 weeks measures about 

 25 inches. 



(c.) Sheep and Goat. The embryo has a length of from 10 

 to 13 inches. 



(cZ.) Pig. The embryo measures about 7 inches in length. 



(e.) Carnivora. The dog's embryo measures about 5 inches ; 

 the cat's embryo, 4 inches. The body is covered with hair, and 

 the claws are present. The eyelids are closed, and the testicles 

 are still in the abdomen. 



VII. Period. Includes, in the horse, the 35th to the 48th 

 week ; in cattle, the 33rd to the 40th week ; in the sheep and 

 goat, the 19th to the 21st or 22nd week ; in the pig, the last 

 half of the loth to the 16th or 17th week; in dogs, the 9th 

 week ; and in cats, the 8th week. In all animals it reaches up 

 to the time of birth. 



(a.) Horse. The foetus attains at the end of this period a 

 length of over a metre (3 feet) ; it is completely covered with 

 hair, and the testicles pass into the scrotum. The inguinal ring 

 is very wide, and slight hernia is generally present. 



(6.) Ox. The foetus measures about 32 inches. 



(c.) Sheep. The foetus has a length of about 18 inches. 

 Goat. The foetus measures about 13 inches; if only one foetus 

 is present, 18 inches. 



(o5.) Pig. The foetus has a length of 10 inches. 



(e.} Carnivora. The foetus measures about 7 inches. The 

 cat's foetus, about 5 inches. 



