1909] Y AM ANOUCHI— MITOSIS IN FUCUS 193 



Fig. 5.— Anaphase: each of the two sets of daughter chromosomes arranged 

 almost in a plane. 



Fig. 6.— Stage similar to -fig. 5, viewed from pole : chromosomes 64. 



Mitoses in the vegetative cells of the female plant 



Fig. 7.— Early prophase of the nucleus in vegetative cells of the thallus: 

 chromosomes (estimated) about 64. 



Fig. 8.— Early metaphase: centrosomes with a few radiations. 



Fig. 9.— Stage similar to fig. 8: chromosomes 64. 



Fig. 10.— Anaphase. 



Fig. 11.— Late anaphase. 



Figs. 12a, 126. — The same stage as fig. 11, viewed from pole: two sets of 

 64 chromosomes. 



Mitoses in antheridia 



Fig. 13.— Developing papilla, to become later an antheridium: nucleus 

 approaching prophase. 



Fig. i 4 —Later stage of papilla: nucleus in anaphase; when this mitosis 

 is completed, there will be formed a stalk cell and an antheridium. 



Fig. 15.— Nucleus of the antheridium in resting condition, showing delicate 

 chromatin network: no centrosome. 



Nucleus with chromatin network beginning to be transformed into 

 a more or less pronounced thread structure: nucleolus without any connection 

 Wlth the ^twork; no centrosome. 



1 , IG " I 7~ N ucleus with first indication of polarity: chromatin thread more 

 .. y tan gtal at one corner of the nuclear cavity; cytoplasm begins to show 

 hnoplasmk nature. 



., IG- l8 -— Nucleus in synapsis: parallel chromatin loops protrude from one 



p ° f nuclear membrane into the nuclear cavity, 

 twd id I9 '~~ Nucleus in synapsis: most of the chromatin loops aggregated at 

 Poles; a few threads traverse the nuclear cavity, connecting the poles; this 

 case is rare. 



». 20.— Nucleus still in synapsis: the loops thickened and shortened. 

 Fi ' 2I -~~ T he same stage, viewed at right angles, 

 nature* 22- ~ Earl y Prophase just after synapsis: chromosomes showing bivalent 



bivalent ? 3- ~~ Propnase: a centrosome at one pole; the two constituents of the 

 nized n mosome com e in close contact, so its double nature cannot be recog- 



Plate - IG ,' 24 ~~ Meta Phase : a number of chromosomes arranged in the equatorial 

 F ' iG Cent _ r °somes with radiations. 



^Iitv hi 5 The Same Sta S e as fig- 2 4> viewed from the P° le ' showln S 32 (i ° 

 F j g Valent ) chromosomes. 



« the do 26 ^ 1 ^ 6 meta P hase: bivalent chromosomes in the equatorial plate 



°f separation, revealing characteristic feature of heterotypic mitosis. 



