DIFFERENT SYSTEMS. g^ 



colour, which beats like a heart. It is vifible at 

 every diaftolc, and difiippears during the iyftole. 

 From this animated point two fmall biood-veilels 

 ifl'uc, and terminate in the membrane which con- 

 tains the tranfparent cryftalline liquor. Thefe 

 blood-veflels Ibt off from the fame place, nearly 

 in the fame manner as the roots of a tree fet off 

 from the trunk ; and it is in the angle which 

 thefe roots form with the trunk, and in the mid- 

 dle of the liquor, that the animated point is fi- 

 tuated. 



Towards the end of the fourth, or beginning 

 of the fifth day, the animated point is fo much 

 enlarged, that it has the appearance of a fmall 

 bladder filled with blood ; and, by its contradions 

 and dilatations, it is alternately filled and emp- 

 tied. On the fame day we diftindly perceive, 

 that this bladder is divided into two parts, each of 

 which dilates and contradls in the fame manner. 

 Round the fhorteft of the blood-veflels defcribed 

 above, a kind of cloud appears, which, though 

 tranfparent, obfcures the view of the velTel. E- 

 very hour this cloud becomes thicker; it attach- 

 es itfelf to the root of the blood-veflel, and feems 

 to depend from it like a finall globe. This globe 

 extends, and appears to divide into three parts, 

 one of which is globular, and larger than the o- 

 ther two; and here wc perceivj the rudiments 

 of two eyes, and of the whole head: And, at 

 the end of the fifth day, we fee, in the remain- 

 der of this lengthened globe, the beginnings of 

 the vertebrae. 



On 



