M.M! i: MI..S oi MM: !.'' AHD : OF 1 BB1 r 43 



- illicit- ir suh-tance. \\hich was desrril >e 1 B 

 MainaMe spherule, there ari 'iilar nucleus (li;_r. :!."> .<,/;, which 



acquires the BUM siz and condition a> the 





Fig. 22. - An egg of Ascaris megalocephala just fertilised, after v \ 



nn-itie IH..IV, with nucleus, which has entered the egg; /, fat-like substance of the 

 :u:itit: body ; kb, germinative vesicle. 



Fig. 23. A stage of a fertilised egg of Ascaris megalocephala, somewhat older than that of 

 fig. 22. ;itVr VAN r.r\i:i>F.x. 



rniatic b:ly, which lias penetrated deejier into the cortex of the yolk ; sp t polar spiinlle 

 wliich luis arisen from the germinative vesicle ; c/i, cliromosomes of tho 



After the rapid and continuous accomplishment of these processes, 

 the egg of the Worm usually enters on a longer or shorter p -riod of 



-i. 



Fig. 24. A still older stage of development, following that of fig. 23. of the egg of Ascaris 

 megalocephala, after H<>VKUI. 



.r j-piiKll.-, whii-h has asivn.l.-d to the surface of the y ( .lk : ./,, _' x 4 chromosomes; 



i ina'if nn. |, MIS, nhicli lia^ inix'r.ited int'i the uiiiUlle of the egg- 

 Fig. 25. Egg of Ascaris megalocephala in preparation for the process of cleavage, after 

 K. VAN HKNEDEN. 



p.ilar cells which liave arisen fn-iu the polar -, 



of the pi-ocess of bu.l.lin-,' : -. - -.: -nu I -us ; sk, spermatic nucleus already preparing to 

 divide ; ch, nuclear loops or chromo- 



It now presents (compare fi<j. -">, which repre- -nts a stage 

 alreatly further developed) at it> surface within the viti-lline mem- 

 brane two polar cell- (/-:. and in its interior two large voA 

 nuclei, the spermatic nucleus (sk) and the eiriMmcleus (ei), the 



