THE OVARY AND THE TESTIS. 129 
matter, which. are developed in different individuals, 
termed males and females. 
These two kinds of living matter are ova and sperma- 
tozoa, and they are developed in special organs, the ovary 
and the testis. The ovary is lodged in the female; the 
testis, in the male. 
The ovary (fig. 30, ov) is a body of a trefoil form, 
which is situated immediately beneath, or in front of, 
the heart, between the floor of the pericardial sinus and 
the alimentary canal. From the ventral. face of this 
Fig. 30.—Astacus flwiatilis.—The female reproductive organs (x 2) ; 
ov, ovary ; od, oviduct ; od’, aperture of oviduct. 
organ two short and wide canals, the oviducts (od), lead 
down to the bases of the second pair of walking limbs, 
and terminate in the apertures (od’) already noticed 
there. 
The testis (fig. 31, ¢) is somewhat similar in form to 
the ovary, but, the three divisions are much narrower 
K 
