V 



the Human Kind and other Animals. 287 



doubt if mola be much less frequent in the mammalia 

 than in the human kind. 



As to Abortion, the instances of this in the family 

 of,animals are very numerous : though not, I presume, 

 so frequent as among the human kind. Abortions, 

 however, are much more common among civilized than 

 among savage nations. And it is well known to Mr. 

 Blumenbach, that a kind of abortus naturally and inva- 

 riably takes place in whole genera of certain orders 

 of the mammalia. This is the case in the common 

 Opossum of North- America ; in the Kangaroes of 

 Australasia, or New-Holland ; and in other animals of 

 the order of Pedimanes, as the French naturalists call 

 them. 



■ 



Cases of Difficult Birth very frequently occur in the 

 class of animals. Nor are these cases confined to a Jew 

 of the mammalia, in a state of domestication. They oc- 

 cur in many of the wild animals. They are not unfre- 

 quent in the class of Birds, especially, perhaps, when in 

 a state of confinement. Thus the Canary-Bird (Frin- 

 gilla Canaria) sometimes dies while endeavouring to 

 part with her eggs. George Seger, one of the pupils 

 of Thomas Bartholine, has shown, that a species of 

 Viper (Coluber Berus?) sometimes excludes her eggs, 

 or young, with great difficulty. In my Anatomy and 

 Physiology of the Rattle- Snake, &c, I shall relate in- 

 stances of a similar kind, in regard to other animals of 

 the class and order of Amphibia Serpentes. Instances 

 of difficult parturition occur even in the great class of 

 Insects. And, indeed, I am inclined to believe, that 



