304 C. ISHIKAWA. 



not lie in the plane of the paper, but a little beneath it. 15y focussing 

 the tube, however, we can distinctly observe the chromosomes as 

 radiating from the pole where the archoplasm lies. A close examina- 

 tion of the chromosomes, represented l)y Figs. 44-47, of the spore- 

 forming individuals, and those. Figs. 33 and 34, of tlie nuclei just 

 liefore division, seems to show that there is some marked difference 

 between the two. While tlie cliromosomes of the nuclei of the divid- 

 ing individuîds are represented by a double row of microsomes, those 

 of the nuclei of the spore-forming individuals appear to consist of 

 four rows (comp. Figs. 47 and oo). This difference is undoubtedly 

 due to the division and the spore-formation. /// divi^iion ilic nucleus 

 lias to dividr onlij once, and lience tlie cliromostwies require onlij 

 once to divide, while in the spore-formation dirisions of tlie nuclei t(d;e 

 place rapidlii one <fter tlie other, and two dirisions tedcc place iduioM 

 simultaneouslij. The w^ay in which two divisions take place simultane- 

 ously can be made out from Figs. 44 and 47, where some of the 

 chromosomes are seen at their ends. The microsomes liecome thicker 

 at their periphery, and form a row of ]'ings. E:ich (-hromatin-i'ing or, 

 perhaps more correctly, the microsome-ring becomes thickened at 

 four ])laces and the interspaces between these thickenings break uj) 

 and thus form four daughter microsomes. Soinctimes the thickening 

 does not take place simultaneously at four places nnd the ring does 

 not break \\\) into four at once, as will be seen in a ring at \\\^ right 

 hand side of Fig. 47, where it is thickened only at one point. An- 

 other ring at the left hand side is broken at one place, and appeiu's 

 C-shaped. A ring represented on the i-ight hand side of the nucleus 

 Fio-, 44, shows a verv interestino; staiiv. This rino- consists of two 

 thick curves connected together by narrow cementing substance — the 

 Z/////i-thread. The ends of these curves are again thickened, showing 

 that the division of the ring into four daughter microsomes does 



