14 CLASS MAMMALIA. 



cient to supply these organs, they cannot turn to their ad- 

 vantage the principal afflux of the blood. The sexual 

 organ is deprived of this derivative action whieh would 

 supply it with an excess of nutriment, and the blood being 

 deprived of this outlet, opens for itself another passage. 

 The crural artery is restrained to the hinge (as it were) of 

 the thigh upon the trunk ; and it is on the branches which 

 are found in this place, that the superabundance of nutri- 

 tious fluid is carried. Thus, by the determination of this 

 artery, a new order takes place, and we find the essential 

 elements of a new family of the animal world. 



In the ordinary Mammalia, when the uterine artery 

 ceases to nourish, the epigastric continues the action ; while 

 the first acts, the superabundant blood is carried from the 

 primitive iliac to its interior branch, from that to the 

 hypogastric, and from the hypogastric to the uterine. In 

 the second case, the blood comes into the exterior branch, 

 and subsequently to the epigastric. Thus the epigastric 

 concludes by a lacteal alimentation what the uterine had 

 begun by a sanguine ; the epigastric being the artery which 

 supplies the abdominal mammae. It is, therefore, by a 

 kind of mathematical necessity, the uterine being deprived 

 of its generative functions, that the blood employing the 

 epigastric at first, must produce in this artery among the 

 Marsupiata, what the progress of organ would produce 

 somewhat later. 



The action of certain imponderable fluids, from the 

 external world, and fecundation, produce inflammation in 

 the sexual organs. The organ which the first of these causes 

 first puts into play is the ovarium, from which this exci- 

 tation is propagated contiguously through each part. This 

 organ having answered its end, in ordinary cases, the 

 uterus provides, by means of the uterine artery, for the de- 

 velopment of the ovarian product. Let us admit, in the 

 case of the Marsupiata, that it is an ovulum traversing a 



