Mr. Gulliver on the Minute Anatomy of Animals. 107 



in a hyperbola. But in such cases the arbitrary quantities 

 introduced by integration cannot be satisfied, unless the mo- 

 tion be in confined spaces or narrow canals, such that the co- 

 ordinates in passing from one point of the fluid to another do 

 not vary independently of each other. These instances are 

 not, therefore, exceptions to the general rule. 

 Cambridge Observatory, June 15, 1842. 



XVIII. Contributions to the Minute Anatomy of Animals. By 

 George Gulliver, F.E.S., fyc. fyc, — No. II.* 



On the Nuclei of the Blood-Corpuscles of the Vertebrata. 

 T> Y subjecting the blood of adult mammals to the slow ac- 

 -*-* tion of a very minute quantity of dilute acetic acid, Dr. 

 Martin Barry states that he has observed nuclei in the cor- 

 puscles, which he has depicted in his recent and elaborate 

 researches on the blood (Phil. Trans., 1841, part 2). Yet it 

 seems fair to conclude that there is an essential difference 

 between the blood -corpuscles of mammals and those of the 

 lower vertebrata, since the very same treatment which never 

 fails to show the nuclei in the latter will not exhibit them in 

 the former. This, as I have elsewhere stated (Appendix to 

 Gerber's Anatomy, pp. 13 and 30), does not prove that the 

 corpuscles of mammals include no central matter, although 

 it induced me to believe that these corpuscles have no nucleus 

 like that contained in the corpuscles of the lower vertebrate 

 animals. 



When the corpuscles of the oviparous vertebrata are mixed 

 with water, or with dilute or strong acetic acid, the nuclei are 

 instantly exposed in the clearest manner, appearing thick, 

 oval or spherical, and much smaller than their envelopes. 

 Several other vegetable acids, and sulphurous acid, may be 

 used with the same effect ; and the nuclei may also be readily 

 shown by gently moistening with the breath some dry blood, 

 which may be again quickly dried so as to preserve the nuclei 

 on the slip of glass for future demonstration. But when the 

 blood-corpuscles of Man and of other mammals, not excepting 

 the oval discs of the Camelidae (Med.-Chir. Trans,, vol.xxiii., 

 and Lancet, vol. ii. p. 101, 1840-41) are treated by any of the 

 means just specified, and precisely under the same circum- 

 stances, no similar nuclei will be observed, unless in very young 

 embryos ; for the corpuscles of these inclose a temporary and 

 obvious nucleus, which is probably the true analogue of the 

 persistent nucleus of the corpuscles of the oviparous vertebrata. 

 In the Philosophical Magazine for February 1840, (S. 3. 



* Communicated by the Author. No. I. will be found in p. 480 of the 

 preceding volume. 



