No. 641] 



TRANSFORMATION OF SEX 



531 



begin to be formed in the germinal epithelium (Fig. 3, c). 

 But during the stage of metamorphosis the slits unite 

 and form only one cavity: the secondary gonad cavity 

 or ova rial sac. In consequence there are in each ovary 

 5 to 7 sacs, forming the thin gonad endothelium (Fig. 7, 

 1,11). 



fhrlnnn. /•■/■/ ^/ >laor.< ni nrnr//f> > iu flir hii raJ period. 



:]. Hii' nl n .^>rnH<l ,l>n,rth intin,l. 4. PyPSeuCC 



of or a rial stirs. 



" chief crit{'i-i(M) of sex (iiftViviitintion."' n> Swiimlc says. 

 On tlie coiitnn-y tlic otlicr tlirc.. aiv iii..n" cliai.-irtcri^ric, 

 because they arc (muiii ilctely al>^fnt in the male line! 



3. The Testis.— In larva' i^i' nun. in Icn-tli uivat (litVcr- 

 ences in the size of the rocd^ aiv I'oniul. as sen t'rom 

 a comparison of Fiu's. 1 and -. Aninnils with llu' -tout 

 ones are undoi-goinu' t raii-l'orniat l(ui inio niah's. 



The testis i^ not t'..i-nicd Ia diiv.-t d.'vrh.ima-nt fiom the 

 indifferent gonad. //^ th r<ln,n,n ,>i n'n^^ inii, a <iia,u,p 

 in the posit urn m tin f/rn>> hiw y>. i ici-iphei-.-d -vr- 



minal e])itlu'liutn ha\iim' di-intruratcd. the -vi'ni r,'!ls 

 cross the ])i-iniit I\ r -onad cav it\ and cntn- Ihr ro-ds 

 (Figs. 4 and 5). TUv i\>\Vu-\v rv\l> migratr with ilw gonia 



