THE ANATOMY OF BIRDS. — OOLOGY. 219 
will be seen that they have a long jouraey to accomplish ; for, liberated in the cloaca of the 
female, they have to swim through the whole length of the oviduct to the ovary. Besides 
such physical difference between the male and female Dynamamoebce as I have indicated, they 
differ in their place and mode of birth ; and in this difference lies the very gist of sex. The 
original indifferent genital gland above described, arrested, as said, at a certain stage of de- 
velopment and therefore female — the ovary — produces its eggs from its surface -cells, which 
subside into the ovarian tissue, and are quietly packed away there as ovarian ova, ready to 
ripen and awaken to impregnation in due course. The same gland, further developed into a 
testis, gives active birth to the spermatozoa in the tubules of its complicated interior tissue. In 
the former case, the superficial cells slowly ovulate ; in the latter, the cells lining the interior 
speedily spermate ; in a word, the testis is as literally viviparous as is the ovary oviparous, — 
and these conditions are certainly no insignificant indices of relative development in the scale of 
being. The spermatozoa appear in some animals to be set free in myriads from the walls of the 
seminal tubules wlience they directly issue ; in birds, they are described as appearing coiled or 
otherwise packed in delicate sperm-cells, which speedily rupture and discharge the creatures in 
the current of the seminal fluid, where they take up the course and display the energetic actions 
above noted. Either case has its parallel among ordinary Protozoans ; the former correspond- 
ing to the process of budding or gemmation, the latter to that of interior fission and discharge 
of numerous progeny by rupture of the envelope. The final conjugation of spermatic filaments 
with ovarian ova is simple fusion, such as any ordinary sexless amoeboid animal may practise to 
blend its protoplasmic substance with that of another. But there is this difference, that in the 
case of Dynamamoeba it is a true sexual congress, usually polyandrous, and still more of a 
one-sided affair in that the female Dynamamceba is at the time in a more or less quiescent, 
encysted state. 
Female Organs of Generation. — The connection between the male and female organs 
of generation is naturally so close that in what has preceded it has been scarcely possible to 
speak of the former without reference to the female counterparts. I have thus far endeavored 
to state clearly the nature of the originally sexless genital gland ; the difference in the same 
gland when afterward sexed male or female ; and the character of the spermatic offspring of 
the male gland. In reading that lesson the novitiate in such Eleusinian mysteries must not 
mistake the language I have used to describe the male Dynamamwba, or spermatozoon, as 
applicable to anything in the development of the female Dynamamoeha, or ovum, into the 
chick ; for all said thus far only relates to the bringing of the spermatozoon into contact with 
the ovum, preliminary to the initial step of the ovum in its course of development. It is this 
female Dynamamceba — this primitive ovarian ovum, the germ of the chick, which con-esponds 
to and is the counterpart of the male Dynamamceba, on meeting and mingling with which 
fecundation is accomplished ; the impregnated ovum being then empowered to take up its 
marvellous march. Conjugation of the opposite Dynamamcebce occurs either in the ovary or 
upper part of the oviduct, — most probably the former. One or several spermatozoa — usually 
more than one — accomplishing their journey up the oviduct, and finding their affinity, 
insinuate themselves into the substance of the ovum, and die there, dissolved in amorous pain; 
that is to say, they melt into the substance of the ovum. The now fertile result, consisting of 
the mingled protoplasm of the opposite amcebas, is to all appearance precisely the same as the 
original infecund ovum — yet there is all the difference in the worid, as the result shows. 
The general character of the ovary of a bird has been already indicated (p. 40). The 
principal superficial difference in appearance when the ovary is in functional activity, from the 
corresponding organ of a mammal, is that the ova develop to such a size, in ripening in the 
ovary before leaving it for the oviduct, that the organ looks like a bunch of grapes, — very 
large and conspicuous. The oviduct is the musculo-membranous tube (modified miillerian 
