408 



shaped forms (seen on edge) appear. The shape is more that of an 

 irregular disc or sphere. The corpuscles are never arranged in rou- 

 leau fashion. 



In the course of an hour, however, one is given opportunity to 

 see a considerable number of individual corpuscles. Under the con- 

 ditions of the experiment one can be certain of a biconcave disc only 

 when seen on edge. Such were seen at least as frequently as typical 

 "cup"- or ''saucer-shaped" forms (also always interpreted from side 

 views). A particularly favorable view was olfered where a capillary 

 of fair size bifurcatel in a Y-shaped fashion. Stasis occurred in the 

 larger stem, and the corpuscles flowed down one limb of the Y and 

 up the other. Here many single biconcave discs were seen, some of 

 which bent slightly (forming what might be called saucer-shaped forms) 

 when passing close to the sharp projection caused by the union of 

 the two limbs. In the smallest capillaries the corpuscles were seen 

 to lengthen out, an adjustment necessitated by the small calibre of 

 the vessel. The writer does not believe that the proof above demanded 

 (and admitted to be the "only proof) can be positively deduced from 

 the source designated, viz., the omentum of a living animal. Under 

 conditions where the individual corpuscles can be seen, the circulation 

 is no longer perfectly normal — and what evidence does appear under the 

 circumstances is equivocal since both biconcave discs and cups, or 

 more properly saucers, are seen. 



Moreover, an examination of Lewis' figures (in Stöhr's Text 

 Book of Histology, 1906, p. 142), upon which his conclusion is mainly 

 based, will show that in both cases the diameter of the vessel is less 

 than the diameter of the discs (supposing the cups to be straightened 

 out), and that the cups are indented in the direction of the current 

 or in adjustment to a bend of the vessel. Assuming that the red 

 blood corpuscle is a very delicate and a very flexible, slightly bicon- 

 cave disc, what other form would it more probably assume under like 

 conditions of limited confines and pressure of current than that of a 

 cup- or saucer-like shape such as shown in Lewis' figures? The shape 

 is exactly what one would reasonably expect; the centre would be 

 pushed out by pressure while the periphery would tend to bend in 

 the opposite direction by reason of friction against the wall. Since 

 it is very generally admitted that the red blood corpuscle is very de- 

 licate and flexible, and since it very frequently has a biconcave disc- 

 shape in the circulation (and predominantly in a hanging drop pre- 

 paration), I believe that the above sketched process is exactly what 

 ■occurs and that the cup-shaped corpuscle is best interpreted as ß, 



