ANATOMY OF BIRDS 



325 



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 

 Dynamamceha — this primitive ovarian ovum, the germ of the chick, 

 which corresponds to and is the counterpart of the male Dynam- 

 ammba, on meeting and mingling with 

 which fecundation is accomplished; 

 the impregnated ovum being then em- 

 powered to take up its marvellous 

 march. Conjugation of the opposite 

 Dynarmmcebm 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 world, as the 

 result shows. 



The general character of the ovary f„ J;°in^°LlivHyfS°ol'raS^? 

 of a bird has beenalready indicated f-^^.^-J'^'j tev^L^^LTrra n™e 



(p. 69). The principal superficial one ; c, its stigma, where the ovisac or 



\.~ ' . „ „l ir,„ calyx ruptures; d, a ruptured empty 



difference m appearance wnen the calyx, to be absorbed ; c, infundibulum, 



nirQT.Tr Jo in fnn^finTial nn+.ivit.v frnm or funnel-shaped orifice of the oviduct ; 



ovary is in lunctionai acUVliy 11 om ^ n^^t portion of oviduct; ff, follicular 



the corresponding organ of a mammal, part of oviduct ; m, mesomeby mem- 



■■^ 1 r J. 1. • brane steadying the oviduct the re- 



IS that the ova develop to SUCn a size, ference-line, m, crosses the constricted 



in ripening in the ovary before leaving |:S,Te'?rtte1vMtro?tSengg'"! 



it for the oviduct, that the organ looks fhe^Wo^.ngor^tennepart^ 



like a bunch of grapes very large or vaginal part of oviduct, opening into 



T . mf -J t. ;„ j-Vin urogenital sinus of the cloaca, n; o, 



and conspicuous. The oviduct is the anul 

 musculomembranous tube (modified 



Miillerian duct) which conveys the ripened ovum, and in its passage 

 provides it with a quantity of white albumen, and finally a chalk shell. 

 A bird's oviduct is the strict morphological homologue (p. 103) of a 

 mammal's Fallopian tube, uterus and vagina— more accurately, of 

 one Fallopian tube, one-half of a uterus, and one-half of a vagina ; 

 for the uterus and vagina of a mammal result from the union of 



