284 CORRESPONDENCE OF RAY. 



particular ; but I would not be quoted against Dr. 

 Lister, lest he should take it ill. 



I never observed the arterial blood of a fish to be as 

 florid as that of quadrupeds. 



I do not think that the venal blood of animals can by 

 any artificial compression or constriction be changed 

 into the colour of the arterial. I am sure that the air 

 immediately changes its colour and consistence upon 

 phlebotomy. 



I cannot answer that of the chicken before exclusion. 

 I wonder Aquapendente, Harvey, Malpighi, and others 

 have not cleared it. 



London, December 20, 94. 



Mr. BURKELL to Mr. RAY. 



SIR, I have, sir, in some of my melancholic hours, 

 been diverted by the Tract I have of yours, and particu- 

 larly your ' Synopsis Animalium,' &c., wherein I observe 

 your opinion settled against equivocal generations, and 

 fol. 1 5, confirmed by many arguments and great authori- 

 ties, yet, if I had leave, I would ask if the species of 

 worms bred in human bodies, or those of brutes, are at 

 any time observed to be generated elsewhere, for I should 

 think it would be hard to say their eggs are conveyed 

 out of one man, or one horse, into another; and the 

 phthiriasis, which I suppose is where worms are bred in 

 the flesh, and which happens to one single man in a 

 nation, and that perhaps once in a hundred years, will 

 be more difficultly answered, where that species of worms 

 or lice do all that time conceal and preserve themselves, 

 and at length light upon this single person. But, sir, it 

 is said by somebody, " Sequimur non qua veritas sed qua 

 ratio trahit :" whether that be applicable here or not 

 I pretend not to determine. I observe likewise, fol. 300, 



