270 1 he Structure of Colored Blood-Corpuscles. 



Soon the granules or dots seem more distinct ; short conical 

 thorns, or more delicate spines, appear to issue from one or two 

 of the largest of them ; and, on close inspection and focussing, 

 some appear to be connected by irregularly concentric filaments. 

 In the course of five minutes more, a complete network is dis- 

 tinctly seen in the interior of one or more corpuscles, and what 

 at first appeared to be granules, turn out to be thickened points 

 of intersection of the threads forming this reticulum. These 

 points or dots are irregularly shaped, and vary in size (see fig. 

 5). Radiary threads of the network terminate at the peri- 

 phery of the corpuscle, either with thickened ends connected 

 by threads — giving an appearance of unevenness to the outer 

 boundary, as though it were constituted by a wreath of beads, 

 each bead separated from its neighbors on the string — or, far 

 more frequently, with terminal points lost in an encircling band 

 of a uniform thickness, often greater than either the interior 

 threads or most points of intersection (compare Nos. 5 and 2 

 of fig. 5). From this appearance, as well as that of the 

 so-called "ghosts," to be presently described, it is not to be 

 wondered at that careful observers have ascribed to colored 

 blood-corpuscles the possession of an investing membrane. 



As the "paling"' progresses, an increasing number of cor- 

 puscles shows the interior network, essentially as I have just 

 described, and identical in construction with the network dis- 

 covered by C. Heitzmann in Amoeba, colorless blood corpus- 

 cles, and other living matter of the body — (" Bau des Proto- 

 jplasmas" Sitzungsberichte der Kaiserlichen Alcademie der 

 Wiskenscliaftm zu Wien, vol. 67, division III, p. 100. Vor- 

 gelegt in der Sitzung am 17ten April, 1873) — a diseovery 

 which I have communicated to the American Medical Associ- 

 ation more than three years ago. 1 



Gradually an interior network structure becomes visible, in 

 nearly all the corpuscles in the field except the smallest, 

 which appear more or less compact ; and, occasionally a cor- 



(1) " Notice of the Bioplasson Doctrine." Transactions of the American Medical Associ- 

 ation, vol. XXVI (1875), p. 157. 



