156 EXTRACTS AND ABSTRACTS FROM FOREIGN JOURNALS. 



and some biscuit- shaped, with their large ends coloured red, and con- 

 taining each a nucleus. These two nuclei were collected together by 

 a thin process, which traversed the uncoloured and canal-shaped inter- 

 mediate portion of the corpuscle. The nuclei of the stalked corpuscles 

 also exhibited a process corresponding to the peduncle of the corpuscle. 

 These observations, therefore, render it probable that in these instances 

 an increase of the corpuscles is effected by means of division. The 

 corpuscles of the embryos of pigs an inch long were four to six times 

 larger than those of adult pigs ; they exhibited double or quadruple 

 nuclei, which probably belong to different divisions of the blood cor- 

 puscle marked by pale intermediate lines. 



To observe the reproduction of the blood corpuscles after losses of 

 blood ; thirty pounds of blood were drawn from a horse, and a part of 

 it when examined was found to contain besides the well known cor- 

 puscles without nuclei, only a few pale lymph-corpuscles, as they are 

 called. On the following day the latter were found in enormous quan- 

 tities and much enlarged ; and in their interior they exhibited one or 

 more pale reddish globules of the size of blood-corpuscles, covered by 

 the granular contents. On succeeding days these globules appeared 

 the more red the more the granular contents of the parent- cells (for such 

 the pale lymph- corpuscles proved to be) diminished, and the thinner 

 their membrane became. On the fourth day, there could be no doubt, 

 that the red blood- corpuscles form within the enlarged pale cells, and 

 become free by the disappearance of the latter. The blood of the 

 horse became, as further experiments showed, the more coagulable, 

 and the thickness of the buffy coat become the greater, the more blood 

 was drawn ; but the buffy coat in such a case consisted of but little 

 coagulated fibrine, with an excessive quantity of the parent-cells of 

 blood- globules. 



I have confirmed these results in near about forty times. Between 

 the fourth and eight days after the first considerable abstraction of 

 blood, even during inflammatory and typhous diseases, the commenc- 

 ing regeneration of blood-corpuscles is seen in the appearance of parent 

 cells, which, as in horses, in consequence of their low specific gravity, 

 are chiefly found in the coagulum of the buffy coat, of which indeed 

 they form a considerable part. My present investigations lead me to 

 expect that I shall succeed in finding easily discernable physical diffe- 

 rences between the buffy coats formed by an excess of parent cells, and 

 those which consist chiefly of coagulated fibrine, and which are the 

 results of the great specific gravity of the blood- corpuscles causing 

 them to sink in slowly coagulating blood. I shall at present only say, 

 that the looseness of the buffy coat is generally the consequence of an 

 excess of new parent-cells. A buffy coat, which appears five days, or 

 perhaps even a shorter time after the first bleeding, can never be a true 

 sign of inflammation. 



With respect to the production of the pale parent-cells, my present 

 investigations render it probable that they are generated, not within 

 the blood, but in the cells which line the walls of the blood-vessels and 

 lymphatics, but experiments in which I am now occupied will deter- 

 mine this. Medicinische Zeitung. July 7, 1841, quoted in Brit, and For. 

 Med. Rev. Jan. 1842. 



