ON GENERATION. 449 



reasonings, of the chalazae standing for the matter of the chick, 

 we have already thrown out in our history, and at the same 

 time have made it manifest that the substance of the chick and 

 its first rudiments were produced whilst the chalazae were still 

 entire and unchanged, and in a totally different situation. 



Neither is it true, as he states, 1 "that the chalazre, ren- 

 dered fruitful by the semen of the cock, stand in the place of 

 seed, and that from them the chick is produced." Nor are the 

 chalazae, as he will have it, 2 " in colour, substance, and bodily 

 properties so like seed, or bear so strong a resemblance to the 

 embryo in a boiled egg, that we may rightly conceive all the 

 parts designated spermatic to be thence engendered." I am 

 rather of opinion that the fluid which we have called colliqua- 

 ment, or the thinner portion of the albumen liquefied and con- 

 cocted, is to be regarded as of the nature of seed, and, if the 

 testimony of our eyes is to be credited, as a substitute for it. 



The observation of this venerable old man is therefore un- 

 necessary when he says,3 " As the whole animal body is made 

 up of two substances very different from one another, and even 

 of opposite natures, viz. hot and cold among the hot parts 

 being included all those that are full of blood and of a red 

 colour; among the cold all those that are exsanguine and 

 white these two orders of parts doubtless require a different 

 and yet a like nourishment, if it be true that we are nou- 

 rished by the same things of which we are made. The sper- 

 matic, white, and cold parts, therefore, require white and cold 

 nourishment; the sanguineous, red, and hot parts, again, de- 

 mand nourishment that is red and hot. And so is the cold 

 white of the egg properly held to nourish the cold and white 

 parts of the chick, and the hot and sanguine yelk regarded as 

 a substitute for the hot and purple blood. In this way do all 

 the animal parts obtain nourishment suitable and convenient 

 for them." Now we by no means admit that the two fluids or 

 matters of the egg are there as appropriate means of nourish- 

 ment for different orders of parts. For we have already said 

 that the heart, lungs, kidneys, liver, spleen, muscles, bones, 

 ligaments, &c., &c., were all alike and indiscriminately white 

 and bloodless on their first formation. 



1 Op. cit. p. 54. 2 Ib. p. 57. 3 Ib. p. 55. 



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