COLOURLESS CORPUSCLES OF THE BLOOD. 417 



in the splenic artery, 1 : 2,260 ; in the hepatic vein, 1 : 170 ; 

 and in the portal vein, 1 : 740. 



Several kinds of colourless morphological constituents can 

 likewise be distinguished in the blood of the Frog* (fig. 74, a) ; 

 namely, the ordinary amoeboid cells, and the so-called 

 granule cells, filled with highly refractile granules. The 

 former (fig. 74) exhibit more, the latter less lively changes of 

 form, associated in freshly drawn blood with locomotive move- 

 ments, and likewise take up into their interior milk globules 

 and particles of colouring matter .-) PreyerJ saw por- 

 tions of the red blood corpuscles of extravasated blood 

 in Amphibia taken up by white blood corpuscles, and thus 

 explained the nature and mode of occurrence of the bodies 

 that were previously called blood-corpuscle-holding cells. 

 When acted upon by induced currents, and the discharges of 

 voltaic electricty, these cells become round, just as occurs, 

 according to Kiihne, in amoebse when irritated. Golubew 

 showed that the cells of the frog, after having been made to 

 contract by the application of a stimulus, recommence their 

 movements. The character of these movements, however, is no 

 longer the same as before the irritation ; for, whilst the pro- 

 cesses are in the first instance conical and finely pointed, on the 

 recommencement of the movement after excitation they are 

 more rounded, as well as shorter and broader, are quickly 

 protruded, and are again withdrawn, to reappear in the imme- 

 diate proximity ; so that a kind of undulation runs round the 

 corpuscle (fig. 74, 6). After a short time, either the original 

 character of the movement reappears, or the corpuscles expand 

 on the recurrence of movements, into a flat disk. When in 

 either of these phases, increased strength of excitation imme- 

 diately causes the corpuscle to reassume the spheroidal form 

 (fig. 74, c). 



* Rindfleisch, loc. cit., p. 21. Kneuttinger, loc. cit., p. 10, et seq. Golu- 

 bew, Sitzungsberichte der Wiener Akademie, Band Ivii., p. 555. 



t Recklinghausen, Virchow's Archiv, Band xxviii., p. 185 ; Die Lymphr 

 gefdsse und ihre beziehung zum Bindegewebe. Berlin, 1862, p. 22. 



\ Loc. cit., p. 423. 



Neumann, Reichert and Du Bois' Archiv, 1867, p. 31. Golubew, loc. 

 cit., p. 555. 



