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RtJCKERT, J 



21-25. !894- 



Anat. Hefte 4:261-351. ph 



J 



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, Chromosome reduction in the microsporocytes of Lilium tigrinum. 



Bot. Gazette 41:183-191. ph. 12, 13. 1006. 



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3o:35i-374- pis. 17, 18. 1897. 



2 5- , Ueber Reduktionstheilung. Sitzungsb. Konigl. Preuss. Akad. V 



18:587-614. figs. 1-4. 1904. 



2 ^- » Zur Frage eines Generationswechsel bei Phaeophyceen. Bot. Zeit. 



64:2-7. 1906. 



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 Pis. 9, 10. 1903. II. The cytology of the gametophyte generation. Annals 



of Botany 18:183-204. ph. 12-14. I9°4. 



630. ph. 40, 41. 1904. 



600- 



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3 °" » Serogenesis in Nephrodium. Bot. Gazette 45:1-3°- P ls - *"* 



1908. 



3I * " ' A Pogamy in Nephrodium. Bot. Gazette 45 : 280-318. figs. 3- 1 9° 8 - 



EXPLANATION OF PLATES VIII-XI 



The figures were drawn with the aid of an Abbe camera lucida, under Zeiss 



irhrnmatiV r\\-.' - -mm tit < . . ... pvrgpt figS- 



pochroma 



r -» v WJ . 1. 5 — jm. A j 3Q> with compensating ocular 12; 



1 12, i 5 -2 9 , 3zat 32a> 34a> JSf 3 ^ 37 ^ 3ga ^ ^ whkh were draw 



pensaung ocular x8; figs. , Sf I4> J0 , JZj ^ ^ ^ ^ J7 , & 39 , 7 

 ^.th ocular 8; and figs. 42, 48, 5 o, 5h 53 , 5 6, 57 , 59 , 60, 63, drawn « 

 ihe plates are reduced to one-half the orginal size. 



drawn 



PLATE VIII 



Figs. ia 

 thall 



•/ 



thallus; no centrosome has appeared, the nucleus is in early prophase and I 



approximate number of chromosomes can be estimated from the two sections 

 near 6a. 



as 



near 64. 



O. 2.— Late prophase: two poles; centrosomes in the center. 



H 



ig. 4 — Metaphase: two sets of daughter chromosomes separa 



ted 



