386 THE BLOOD, BY ALEXANDEE ROLLETT. 



versing the angles of division of the vessels, were facts well 

 known to the older observers. 



Lindwurm,* in thick solutions of mucilage; Hassall/fin micro- 

 scopic coagula ; and Henle,J in thick semi-fluid jelly, all saw 

 the blood corpuscles assume a distorted or elongated and some- 

 times an extremely elongated fusiform shape. 



The greatest variety of such forms is obtained when defibri- 

 nated blood is imbedded in pure solution of gelatine, melting at 

 35to 36 C. (95 to 97 F.) ; from which, again, when it has become 

 stiff, fine sections can be prepared, and placed under a covering 

 glass; we may here particularly observe in such sections through 

 the clefts of the gelatine, how the parts of the corpuscles drawn 

 out into various forms, and often much attenuated, are always 

 pale, and often even without perceptible colour ; whilst the 

 swollen parts appear, on the other hand, more deeply tinted. 

 Long processes extend from some of the corpuscles, which ulti- 

 mately divide without coalescing with others. The nuclei of the 

 elliptical blood corpuscles are somewhat less yielding, and they 

 are frequently found to be completely detached from the substance 

 of the blood corpuscles ; these, however, in many instances, as 

 is deserving of special mention, do not in consequence suffer any 

 notable change, either in their diameter or in their capabilities of 

 resistance. Instances of the mechanical influences inducing 

 change in the form of the red corpuscles occur, as already pointed 

 out, in the movement of the blood while circulating. E. H. 

 Weber,|| in 1830, adduced his own observations upon this point, 

 and referred to the numerous ones made previously to the time 

 of Leeuwenhoek. 



The phenomena may be well seen in examining the circulation 

 in the membrane of the foot, and in the tongue or mesentery 

 of the frog. 



According to Rollett, in the circulating blood of Mammals, as, 

 for instance, of guinea-pigs, that have been narcotised with 



* Zeitschrift f'dr rationelle Medicin, Band ~vi., p. 266. 

 f Microscopic Anatomy, p. 31, et seq., plate ii., fig. 6. 

 J Canstatt's Jahresberichte, 1850, Band i., p. 32. 



Rollett, Sitzungsberichte der Wiener Akademie, 1862, Band xl., 

 vol. i., pp. 6571. 



II Handbuch der Anatomic, Band i. Braunschweig, 1830, p. 159. 



