436 
The Ohio Naturalist. 
[Vol. VI, No. 3, 
with a central opening in the sixth segment; pairs of sperma- 
tothecae in the third, fourth, and fifth segments; and a clitellum 
confined to the ventral surface of the fifth, sixth and seventh 
segments. 
Among a number of individuals of an undescribed species of 
Aelosoma, taken from the vivarium of the University of Penn- 
sylvania about December 1st, 1901, ten were found containing 
the sex products in various stages of development. Of these 
three were hermaphroditic, four contained ova alone, and three 
male sex cells alone. Thus while this species is plainlv her- 
maphroditic, it seems probable that eggs and sperms do not 
mature simultaneously in the same individual. The occurrence 
of ripe spermatozoa, (represented in Fig. 5), and immature ova 
in the same individual indicates that the species is protandrous, 
but the evidence is insufficient to decide this question. Many 
of those in which sex cells were found were also reproducing 
asexually in the usual manner. 
The ova, (Fig. 1), are found in the fifth, sixth, and seventh 
segments, in some cases in only one of these segments, in others 
in all three. One individual, however, contained ova in the 
fourth, fifth and sixth segments. They are attached to the thin 
peritoneal layer lining the body cavity, and lie below the stom- 
ach and lateral to the ventral blood vessel, In Fig. 1 the larger 
of the two ova represented is by far the largest observed, measur- 
ing ca. 55 micra across, and is probably approaching maturity. 
It occupies a median position, compressed between the stomach 
wall (st.) and the ventral hypodermis (hyp.), the walls of the 
ventral blood vessel (b. v.) having been ruptured. The smaller 
ovum occupies the usual position. Both ova possess a vesicular 
nucleus (germinal vesicle) containing scattered chromatin 
granules and a large nucelolus, enclosing a vacuole. The cyto- 
])lasm is packed with deeply staining yolk granules. The num- 
ber of ova is small in all of my preparations, one of the best 
showing only eight in the three ova-bearing segments. No 
evidences were found of an oviduct, a clitellum, or of sperm- 
atothecae. 
Although no clear evidence of the presence of testes was found 
the ripening male sexual elements (Figs. 2-5) were seen floating 
free in the body cavity, being found in greatest abundance near 
the point where stomach and intestine join. They appear as 
groups or nests of cells, more or less spherical in form. Four 
kinds of these can be readily distinguished by the character of 
their component cells ; the primary spermatocytes, the secondary 
spermatocytes, the spermatids, and the spermatozoa. The 
primary spermatocytes, (Fig. 2), form cell nests made up of 
comparatively few cells, in size the largest of the series, their 
nuclei measuring ca. 3.9 micra in diameter. As Fig. 2 shows, 
