On the Spermatophores of Octopus Americana. 37 
is likely to occur, they may be placed in a diffusion apparatus with 
glycerine over night and mounted in glycerine jelly the next day. 
I have found a very simple diffusion method with glycerine is to 
place the spermatophores in a concave watch-glass filled with formalin. 
Place this in a shallow stender dish of about the diameter of the 
watch-glass, fill the space between the two dishes with glycerine and 
flood with formalin, so that the diffusion may take place over the 
edge of the watch-glass. 
Specimens mounted in glycerine jelly will be clearer than those in 
formalin and may be studied at leisure. The stain fades slowly, but 
is sufficiently permanent to be effective some months. 
STRUCTURE. 
The spermatophores of Octopus differ in size with the size of the 
individuals from which they are taken. Large ones measure as much 
as 50 mm. in length, small ones may not be more than two-thirds as 
long. The spermatophores are slender and taper irregularly from the 
aboral to the oral end. The sperm mass (fig. 1 sm), which is white 
and opaque, lies in the aboral end of the spermatophore and occupies 
about one-third of its length. The ejaculatory apparatus occupies 
between one-third and one-half of the oral end of the spermatophore 
and is quite transparent. 
Between these two portions and extending along the sides of the 
sperm mass and ejaculatory apparatus is a space occupied by liquid 
in which is a considerable mass of granular material (fig. 1 z). This 
material mixes readily with water and it may have an important 
osmotic property. The bulk of it occupies a position between the 
sperm mass and ejaculatory apparatus that corresponds to the position 
of the cement body in the squid, but it evidently has no cementing 
property and is not inclosed in a special capsule. No cement is needed 
in this spermatophore, as the sperm are not loaded by the ejaculating 
spermatophore into a sperm reservoir that has to be stuck into posi- 
tion, but are evidently introduced directly into the oviducts of the 
female. Whether there is any homology between these materials in 
the two forms is not clear. Their similar positions are significant but 
their functions are evidently entirely different. 
The spermatophore is turgid and elastic but not nearly so much so 
as the spermatophore of the squid, which is so turgid that when bent 
it will, upon release, assume its original shape immediately. The 
squid spermatophore may even be picked up by one end with forceps 
and will stick straight out without appreciably bending. The octopus 
spermatophore may be bent into flowing curves on the bottom of a 
dish and remain as left, provided none of the curves are abrupt. It 
is nevertheless under considerable tension, for when the outer cover- 
ing of a fresh spermatophore is cut, the contents are thrown from 
