212 



OF THE BLOOD AND CIRCULATION. 



(fig. 229). In these vessels the round lymph-corpuscles 

 f,0,a,0) are seen swimming under, over, and behind the oval 



blood-discs (b, b), 

 both of them pro- 

 ceeding paripassu 

 here, and having 

 the same mode- 

 rated motion : still 

 it is impossible not 

 to observe that the 

 blood-corpuscles 

 are possessed of a 

 greater degree of 

 lubricity, that they 

 evidently glide 

 more readily over 

 one another and 

 over the smooth 



//^V' \/l!// ^V/V\C~H55^ walls of the ves- 



//YV&Lj/y ^ r^S^^J _ S els, than the 



lymph-corpuscles, 

 which seem often 

 to get set fast at 



the bendings of 

 Fig. 229. View in outline of a large vein of the ,1 1 1 <- 



frog's foot magnified GOO times. The blood-glo- Ls ' 



bules, b and c, present sometimes their thin edges, 

 sometimes their broad surfaces, here they lie pa- 

 rallel, there diagonally, and elsewhere athwart the branches are 

 course of the vessel. The lymph-globules, a, a, are 

 principally conspicuous in the clear space near the 

 walls of the vessel. 



I 



the angles where 

 anastomosing 



re- 

 ceived or given 



/r .-, .-, 

 off tnere , ^ey re- 

 main sticking tor 

 an instant, and then are suddenly carried on again. Single 

 blood-corpuscles, too, may frequently be observed hurled 

 by a wave, as it were, against angles of the containing 

 vessels, and remain hanging for a brief interval ; at these 

 times they may be seen quivering or oscillating, in spite 

 of the pressure they must undergo ; but their stoppages 

 are never long, they soon fly off again, or, becoming in- 

 volved in the general stream, they are borne onwards. In 

 tAniiumplating the circulation under these circumstances, a 

 byeciacle of the most interesting kind is presented to the eye: 



