290 HISTORY OP 



to increase ; the head appears with two little bladders, in the 

 place of eyes ; the heart beats in the manner of every embryr 

 where the blood does not circulate through the lungs. In abo 

 fourteen hours after this, the chicken is grown more strong ; ' 

 head however is still bent downwards ; the veins and arteries beg i 

 to branch, in order to form the brain ; and the spinal marrow •' 

 seen stretching along the backbone. In three days the vvh' . 

 body of the chicken appears bent ; the head with its two e; 

 balls with their different humours, now distinctly appear ; ai 

 five other vesicles are seen, which soon unite to form the ruf r 

 ments of the brain. The outlines also of the thighs and wii > 

 begin to be seen, and the body begins to gather flesh. At 

 end of the fourth day, the vesicles, that go to form the bra '>■ 

 approach each other; the wings and thighs appear more sol n' 

 the whole body is covered with a jelly-like flesh ; the heart t ,? 

 was hitherto exposed, is now covered up within the body, b i' 

 very thin transparent membrane ; and, at the same time, t 

 umbilical vessels, that unite the animal to the yolk, now app- u 

 to come forth from the abdomen. After the fifth and s' iv 

 days, the vessels of the brain begin to be covered over; t^ 

 wings and thighs lengthen ; the belly is closed up and tuir n 

 the liver is seen within it very distinctly, not yet grown red; 'i. 

 of a very dusky white ; both the ventricles of the heart are o 

 cerned, as if they were two separate hearts, beating distinci 

 the whole body of the animal is covered over ; and the trr ,i 

 of the incipient feathers are already to be seen. The sev< ■• 

 day, the head appears very large ; the brain is covered enti h 

 over ; the bill begins to appear betwixt the eyes ; and the wi .( 

 the thighs and the legs, have acquired their perfect figui >! 

 Hitherto, however, the animal appears as if it had two bodie 

 the yolk is joined to it by the umbilical vessels that come frc 

 the belly, and is furnished with its vessels, through which t) 

 blood circulates, as through the rest of the body of the chickei 

 making a bulk greater than that of the animal itself. But to 

 wards the end of incubation, the umbilical vessels shorten tl- 

 yolk, and with it the intestines are thrust up into the body of t\ 

 chicken by the action of the muscles of the belly ; and the tw 

 bodies are thus formed into one. During this state, all the oi 



1 Haller. 



