No. 472] 



POLLEN GRAIN VARLATION 



259 



Both of the two truths presented by Tschistiakoff were either 

 denied or ignored by later writers, (Strasburger, 78; 'SO). While 

 Juranyi ('82) mhnitted TschistiakofY's view of the origin of the 

 small cells, proving it in Cycads, and believing it true for Con- 

 ifenie, both Juranyi and Strasburger believed the hiruc tube cell 

 of the pollen grain furnished the male gaiiictis and therefore 

 represented an antheridium, and it was not until Rclajctl' i 'IH '03) 

 proved the contrary for Taxus haccata that the correct view was 

 finally established, and generally accepted. Both Belajeff ('91- 

 '93) and Strasburger ('92) showed that in the Abietinere also it 

 was not the tube cell, but the end cell of the row of interior cells 

 formed, from which the male gametes were derived. Str;isl)nrger 

 ('84) hatl previously admitted that Tschistiakoll's view ..f the 

 origin of the small cells in the pollen was correct, and he ha l also 

 shown that in Larix europoea the third small cell cut off from the 

 large pollen cell divided into two cells which he named the "stalk" 

 (see Meyen, '39, p. 189) and "body" cells respectively. The 

 recognition of the "splits" in the wall of Larix ])ollen as disin- 

 tegrating vvWs (',S4, pp. was a conhrniatioti of the earlier 

 views of Schacht and :\leycii. 



abs„rl,ed and yet two permanent ones are found. AKo pollen 

 grains were rep"eate<lly observed in which there were tluve perma- 



nent inner cells preceded l.v one ahsorhe.l cell. Finally one grain 

 was seen in which all three" pn.thalliuin cells were permanent, and 

 the first of the.se was divi.le.l longitudinally. .Vlso (Strasbinger, 

 '92, p. 18) the stalk cell of the antheridium ai)pears to divide tmder 

 some circumstances. 



Since 1893 the most important step in the progress of our knowl- 

 edge of the j)()llen of gynmosperni> was the discovery of motile 

 spermatozoids in istHi and |S!)7, l.v Ikeiio r\)s< in ( vca^. by 

 Hirase f'97) in (iinkgo. and bv Webber , ••♦7 > in Z;u.na. Webbers 



point of view of variation in thos.> genera. lie did not work out 



