SEXUAL ACTIVITIES OF THE SQUID 413 
ment and become arranged in groups of from twenty to forty 
or more, parallel to each other and filling the lumen of the duct. 
Thus, when they are ejected from the penis and grasped by the 
hectocotylized arm, an even group, with their aboral ends for- 
ward and the threads still embedded in the secretion of the penis, 
is presented to the grasping arm. 
SUMMARY 
Spermatophore structure. The contents of the spermato- 
phore are referred to as the sperm mass, cement body, and ejac- 
ulatory apparatus. 
The sperm mass consists of the spermatozoa surrounded by 
and mixed with a mucilaginous material which mixes readily 
with water. It is the proper delivery of the sperm mass that 
is the essential action of the spermatophore. 
The cement body contains the sticky material that finally 
sticks the reservoir, into which the sperm mass is forced, in 
position on the female. 
The ejaculatory apparatus consists of membranous’ tubes 
and structures that together form by their evagination, the 
conducting tube through which the cement body and sperm 
mass are forced, and the sperm reservoir into which the sperm 
mass is forced. 
The contents of the spermatophore, as described, are en- 
closed inside a very elastic outer tunic and a middle tunic that 
is elastic and capable of taking up water rapidly. Together 
these tunics supply the power necessary for ejaculation of the 
spermatophore. 
The outer tunic is closed by a cap which is cemented in posi- 
tion and may be loosened by pulling the thread connected with 
the cap. 
Spermatophore ejaculation. When the cap loosens the force 
supplied by the elastic outer tunic and osmotic middle tunic 
causes the ejaculatory apparatus to evaginate. In doing so the 
two outer coats of this apparatus, the inner tunic and the outer 
membrane, are reflected to form the sperm reservoir into which 
the sperm mass is forced. The continued action of the outer 
