570 DR. NELSON ON THE REPRODUCTION OF THE ASCARIS MYSTAX. 
Having- now fully traced the formation of the spermatic particles, from the nu- 
cleated granule, thrown off by the csecal extremity of the testicular tube (Plate XXV*. 
fig. 8 d) to the flask-shaped body met with in the oviduct (Plate XXVI. fig. 38), I now 
pass to the description of the female organism, previous to entering on the develop- 
ment of the ovum. 
The female Ascaris, as I have already said (Plate XXV*. fig. 4), is larger than the 
male (fig. 3) ; its tail also is straight (fig. 4 a) and not curled up (fig. 3 a). 
The orifice of the vagina (Plate XXX. fig. 91 a) is placed about one third the length 
of the animal from the head ; it is a simple circular opening, but so small as to be 
seen with the greatest difficulty. The ovarian tubes, on the other hand, may be 
seen filling the body with convolutions, reaching from the tail to within a short 
distance of the head. 
The reproductive apparatus is not firmly fixed in one position, but moves back- 
wards and forwards with considerable facility in the space between the intestinal 
tube and integument. 
The following is the method I employed for the extraction of these generative 
tubes. Cut off the head and neck a little above the convolutions, and seizing the 
tail with forceps, by very gradually increased pressure, commencing at the tail and 
passed along the body towards the cut extremity, squeeze out the whole visceral con- 
tents, leaving nothing but skin behind. 
To prevent entanglement of the different parts it is best to effect this expression 
under water. When it has been accomplished, with needles unravel the convolutions 
and remove the intestinal canal, which is easily recognised by its straightness and 
great relative diameter. If carefully performed, we obtain two very long, almost 
capillary tubes (fig. 92 a, h, c, d), which after enlarging (fig. 92 f) become united into 
one canal (tig. 92 g), whose termination has already been described as the generative 
orifice (fig. 91 a). 
On examining the reproductive apparatus (fig. 92) we observe it to be composed of 
several portions, differing in appearance as well as structure. 
These tubes commence near the tail in two extremely delicate csecal ends (fig. 92 a), 
gradually increase in size as well as in opacity, and after performing various convo- 
lutions backwards and forwards throughout the greater part of the body (fig. 92 i) 
they suddenly become constricted (fig. 92 c). This opake portion is the ovary, or 
rather the ovarian tube, and is from 4 to 6 inches in length ; it is followed by an 
almost transparent piece from a quarter to half an inch in length, with a constric- 
tion at either end, separating it from the ovary on the one side and the part that im- 
mediately succeeds on the other (fig. 92 c, d). Each tube now becomes greatly 
dilated, so as to be several times the diameter of the former portions, forming what 
are termed the uteri (fig. 92 f). 
The uteri are also half an inch long, lie parallel to each other, and unite together 
to form a vagina of about the same length (fig. 92 g). The opacity of the ovaries, uteri, 
