Spermatophore of Dardanm asper — MATTHEWS 
259 
Fig. 5. Dissection of right vas deferens showing exact nature of the coils, a, Posterior region of right testis; 
b, (1, 2, 3) indeterminate region; c, first right-handed coil; d, first left-handed coil; e, second right-handed coil; 
f, region of fragmentation of the sperm column; g, compact left-handed helix; h, flat spiral; /. enlarged, highly- 
contorted region. (6X.) 
Even when the internal mass is vitally stained, 
the result of these many and varied contrac- 
tions on the formation of the spermatophore 
is difficult to perceive. However, the internal 
mass, regardless of what portion of the vas 
deferens is observed, appears to respond to 
the ever-changing, restless wall. The com- 
bined effect seems not so much to move the 
mass along as to mold it to an internal die. 
If the activity which is seen in the altered vas 
deferens approximates the activity which is 
obscure in the unaltered vas deferens, sperma- 
tophore formation in D. asper is a slow and 
complicated process. During the course of an 
hour the internal mass rarely moves more than 
a few millimeters. This mechanical activity, 
brought about by contraction of the muscular 
fibers, must be correlated with the morpho- 
logy and physiology of the vas deferens if 
the process of spermatophore formation is to 
be understood. 
Correlation between Morphology, 
Physiology of Epithelial Cells, and 
Contractions of Muscular Walls 
of the Vas Deferens 
The region of the vas deferens (Fig. ‘5bl) 
which receives the sperm from the testis pre- 
sents in cross section (Fig. 6) a tube whose 
muscle layer {a), epithelial layer {b), and lu- 
men (c) are little specialized. The muscle wall 
is thin. The cuboidal epithelium is evenly 
distributed around a cylindrical lumen which 
contains loose clusters of spermatozoa {d). 
The cuboidal epithelium secretes a substance 
{e) which enters the lumen and mixes freely 
with the spermatozoa. Whether this substance 
serves as a nutrient or as a lubricant was not 
ascertained. The muscular activity, revealed 
by the dissecting microscope, serves not only 
to move the sperm mass and to mix it with 
the epithelial secretion but also to mold the 
mass in compliance with the cylindrical lu- 
men. 
Gradually the internal morphology of the 
vas deferens changes. From the indeterminate 
region (Fig. 5^2) a cross section (Fig. 7) re- 
veals that the cuboidal epithelium has given 
way to columnar epithelium (b) except at two 
Fig. 6. Cross section through the indeterminate re- 
gion of the vas deferens (Fig. 5^i). a. Muscular layer; 
b, cuboidal epithelium; c, cylindrical lumen; d, loose 
clusters of spermatozoa; e, secretion produced by epi- 
thelial cells. (54 X.) 
