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part the extent of the alternate lateral divergences is about 
equal to the thickness of the hair, bu t t they are absent for 
some distance both from the base and tip. The bulb is 
glassy and transparent, showing no structure, flask-shaped, 
and joined to the body of the hair by a rather long, slender, 
transparent neck. All this glassy part is embedded in the 
skin, and, at the point where the hair projects beyond, it 
suddenly swells out to its full thickness, forming a hemi- 
spherical base. A remarkable character of these hairs is 
their singular lightness, which may be seen by letting them 
fall from the hand, when they float through the air like 
feathers. With the exception of the bulb, the entire hair 
has a cellular structure, and what might be called its cortical 
portion is nothing more than a surface-layer of small poly- 
gonal cells without any appearance of horny substance, 
while all the inner parts consist of a very coarse cellular 
structure in which no regularly-shaped cells can be seen, 
but there is rather the appearance of shapeless cavities 
separated by very thin membranous partitions. This inner 
structure is so delicate that the hair can be crushed in and 
flattened by very slight pressure, though there can be no 
doubt that its strength is greatly increased by the wavy 
form already mentioned, this being an arrangement similar 
to the ridge-and-furrow of iron structures, which is so 
important an element of their strength. Dr. Carpenter, in 
his work on the Microscope, mentions that the hair of the 
Reindeer has a very similar structure to that of the Musk ; 
it appears, in fact, to be identical in plan, and this complete 
cellular structure, so different from that of ordinary hair, is 
found not only in the Reindeer, but in the common Stag, 
the Rusa Deer, and the Roebuck, that of the Roebuck show- 
ing the nearest approach in general character to the hair of 
the Musk-deer. With regard to the Caribou, which may be 
presumed to have hair of similar structure to that of the 
European Reindeer, the statement of Dr. Richardson that 
