406 ON GENERATION. 



minute point situated in the centre of his figure of the chick 

 of the fourth day, without stating, however, that it had any pulsa- 

 tion ; and this he did not perceive to be the heart, but rather 

 believed it to be the rudiment of the body. It is certain, there- 

 fore, that Fabricius spoke only from conjecture and precon- 

 ceived opinion of the origin of the liver ; even in the same way 

 as others have done, Aldrovandus and Parisanus among the 

 number, who, lighting upon two points, and perceiving that 

 they did not pulsate simultaneously, straightway held that one 

 was the heart, the other the liver. As if the liver ever pulsated, 

 and these two points were aught but the two pulsating vesicles 

 replying to each other by alternate contractions, in the way 

 and manner we have indicated in our history ! 



Fabricius, therefore, is either deceived or deceives, when he 

 says, "In the first stage of the production of the chick, the 

 liver, heart, veins, arteries, lungs, and all the organs contained 

 in the cavity of the abdomen, are engendered together ; and in 

 like manner are the carina, in other words, the head with the 

 eyes and entire vertebral column and thorax engendered." For 

 the heart, veins, and arteries are perfectly distinguished some 

 time before the carina ; the carina, again, is seen before the 

 eyes ; the eyes, beak, and sides before the organs contained in 

 the cavity of the abdomen ; the stomach and intestines before 

 the liver or lungs ; and there are still other particulars connected 

 with the order of production of the parts in generation, of which 

 we shall speak by and by. 



He is also mistaken when he would have the vegetative por- 

 tion of the vital principle prior in nature and time to the sen- 

 sitive and motive element. For that which is prior in nature 

 is mostly posterior in the order of generation. In point of 

 time, indeed, the vegetative principle is prior ; because without 

 it the sensitive principle cannot exist : an act if the act of an 

 organic body cannot take place without organs; and the 

 sensitive and motive organs are the work of the vegetative 

 principle ; the sensitive soul before the existence of action, is 

 like a triangle within a quadrangle. But nature intended that 

 that which was primary and most noble should also be primary ; 

 Avherefore the vegetative force is by nature posterior in point of 

 order, as subordinate and ministrative to the sensitive and mo- 

 tive faculties. 



