•4. 



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 th 



e 





Ions 



evv 



th 



e 



F 



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nich 

 tory 



be- 



and 



and 

 the 



erial 



;air 



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co- 

 'ith 



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 -five 



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oa 



oik 



:hick 



Sect. III. I. 5 



UMBILICAL VESSELS 





ba 



o 



H 



times, I fuppofe, before its nativity, as the chick perforates the air- 



and is heard to chirp, before it is excluded from the (hell, 

 nee it would appear, that both the artery attending the femintl 

 )ts above mentioned, and this artery on the chorion of the chick, 

 ift perform fome more important office than to fupply nourifliment 

 the coats of the abforbent vefTels, which imbibe the mucilage of 



and which abforbents muft them- 



, And what more important 





m 



feed, or the white of the eg 



felves poflefs their proper vafa vaforum 



office can they have than that of oxygenating the blood of th 



table or animal embry 



? And this becomes more probable as they 



both peri'Oi at its nativity like the placenta and cotyledons of 



parous anima 



Is. 



5. As- the incubation of the chick advances, it differs from the {tt^ 

 embryon in the produ6lion of inteflines, with a flomach, on the in 

 ternal furfaces of which the mouths of the abforbents now terminate 



i' 



th 



to receive and 



and laftly in the produdlion of a mouth and 

 fwallow the remainder of the albumen, in which it fwims ; whereas 

 the feed- embryon fhoots down new roots into the earth with an ab- 

 forbent fyflem to acquire its nutriment, as that from the cotyledons 

 of the feed becomes exhaufled. See Sed. VII. 1,2. 



Nor is there anything fimilar to the yolk of the egg found in the 

 feeds of veo;etables, which is drawn up into the inteflines of the young 



chick about the time of its exclufion from the fhell to ferve it with 



nutriment for a day 



of its parent by 



to fele6l and fwallow its adapted food. Nor is the fetus of vivipar- 

 ous animals furnifhed with any thing fimilar to the yolk of oviparous 

 ones, as they have milk ready prepared for their firft nutriment in 

 the breafl of the mother. 



As foon as the new foliage of the plant rifing out of the ground 



- 



becomes expanded, and the root defcending penetrates the earth with 

 its fibrous ramifications, the umbilical fyflems of vefTels ceafe to adl, 

 both the abforbents, which previoufly fupplied the young embryon 



fe 



E 



with 



