288 ' The Structure of Colored Blood- Corpuscles. 



pretty strong solution, and found to corrugate the vesicles." 

 The vesicular nature of colored blood corpuscles, thus an- 

 nounced more than sixty years before the publications of 

 Schleiden and Schwann, so perfectly fits into their cell-schema, 

 that many suppose that they have originated this view 

 of the constitution of the corpuscles. Bat in point of fact 

 they have in this respect followed Hewson. According to 

 Schwann^ 1 the red blood-corpuscle is a cell and consists, like 

 every other cell of the body, of a membranous envelope, a 

 nucleus, and liquid contents ; the credit of the observation of 

 the " rolling around " of the nucleus is given by Schwann 

 to C. If. iSchultz, who, however, has only repeated and con- 

 firmed 2 the experiments of Hewson. 



Although not accepted without some opposition, it was not 

 until the year 1861 that the existence of a cell-wall was posi- 

 tively denied. Beetle declared : 3 " I have never succeeded in 

 seeing the cell-wall said to exist, neither have I been able to 

 confirm the oft-repeated assertions with regard to the passage 

 of liquid into the interior of the corpuscle by endosmose, its 

 bursting and the escape of its contents through the ruptured 

 cell-wall. When placed in some liquids, many of the cor- 

 puscles swell up and disappear; but I have never seen the 

 ruptured cell walls." He also published observations which 

 he considered "fatal to the hypothesis that each corpuscle is 

 composed of a closed membrane, with fluid contents." 4 Briicke 

 expressed the opinion that the rolling around of the nucleus 

 is illusory, that other phenomena do not conclusively prove 

 the presence of a membrane, and that " the unanimity with 

 which the vesicular nature of blood-corpuscles had for a long 



(1) MikroskopischeUnter6uchungenuber die UebereinstimmunginStructur und Wachs- 

 thum der tbierischeu und pfianzlichen Organismen. Berlin 1839 pp 74 und 75. 



(2) Das System der irculation. tstuttgardt aud Tubingen. 1 36 p 19 etseq. 



(3) * Lectures on tbe structure and growth of tte tissues of tbe human body. Delivered 

 at tbe Royal < o.lege of Physicians. Lecture III. April 22nd 1861." Archives of Medicine 

 vol. II. No. 8 ( May, 1 61). p 236 Re published in Quarterly Journal of Microscopies 

 Science vol I N. S. (April-May, 1861; p. 240. 



(1) Otnervatioa^ upja the nit ire of the red blood-corpuscle " Transactions of the Micr 

 Soc, vol. XII, N. S. p. 37. Quarterly Journal of Microscopical Science Jan., 1864. 



