386 
upon, the corpuscles now containing sulphemoglobin, as 
indicated by the persistence of two lines of oxyhzemoglobin, 
together with a new line in the red having a definite posi- 
tion, which was duly compared and recognised. It is inte- 
resting to find that sulphemoglobin, like hemoglobin, does 
not diffuse from the corpuscles under normal conditions. 
If we compare now the reagents which affect the hemo- 
globin of the blood-corpuscles, we find them acting very 
differently. 
Causing its discharge: 
Unchanged.—Chloroform, O83, benzine, &c. Ammonia (in very small 
quantity). Water (requires time). 
Changed —Cyanogen (Cyanhematin), Ammonia (alkaline hematin). 
Not causing its discharge : 
Not changing.—Alcohol (or only to methemoglobin) but precipi- 
tating. 
Changing.—Carbonic oxide (CO hemoglobin). Sulphuretted hydrogen 
(sulphemoglobin). Acetic acid (acid hematin). 
General conclusions and summary.—The red blood-cor- 
puscle of the vertebrata is a viscid and at the same time 
elastic disc, oval, or round in outline, its surface being diffe- 
rentiated somewhat from the underlying material, and 
forming a pellicle or membrane of great tenuity, not dis- 
tinguishable with the highest powers (whilst the corpuscle 
is normal and living), and having no pronounced inner limi- 
tation. The viscid mass consists of (or rather yields, since 
the state of combination of the components is not known) a 
variety of albuminoid and other bodies, the most easily separable 
of which is hemoglobin ; secondly, the matter which segre- 
gates to form Roberts’s macula; and thirdly, a residuary 
stroma, apparently homogeneous in the mammalia (excepting 
so far as the outer surface or pellicle may be of a different 
chemical nature), but containing in the other vertebrata a 
sharply definable nucleus, this nucleus being already dif- 
ferentiated, but not sharply delineated during life, and con- 
sisting of (or separable into) at least two components, one 
(paraglobulin) precipitable by Co,, and removable by the 
action of weak NH,; the other pellucid and not granulated 
by acids. 
The chemical differentiation of the outer pellicle is rendered 
probable by the behaviour of the corpuscles under weak NH,, 
which appears to dissolve this pellicle, and so loose the viscid 
matter from that which restrained it to its oval shape; also 
from the inability of CO, to act on the corpuscle until it has 
