204 INTRODUCTION TO EMBRYOLOGY OF ANGIOSPERMS 



and Nicotiana (Goodspeed, 1947); three in Statice (Dahlgren, 1916), 

 Gossypium (Iyengar, 1938), and Orchis (Hagerup, 1944); and as 

 many as five in Juglans (Nawaschin and Finn, 1913). 



The entry of additional pollen tubes naturally results in the 

 release of supernumerary male gametes inside the embryo sac. 

 Rarely, one and the same pollen tube may also carry more than 



two sperm s . This abnormality 

 may originate either in the pol- 

 len grain or in the pollen tube. 

 To mention a few examples, 

 three sperms were sometimes 

 seen in the pollen grains of Cus- 

 cuta epithymum (Fedortschuk, 

 1931) (Fig. 99C); and four in 

 Helosis cayennensis (Umiker, 

 1920), Vinca herbacea (Finn, 

 1928a) (Fig. 99K), Parthenium 

 argentatu?n, and P. incanum 

 (Dianowa, Sosnovetz, and Stes- 

 china, 1935). Four sperms 

 have also been seen in the 

 pollen tubes of Allium rotun- 

 dum, A. zebdanense (Weber, 

 1929), Galanthus nivalis (Tran- 

 kowsky, 1931), Crepis capil- 

 laris (Gerassimova, 1933) (Fig. 

 117.D), and Polygonatum canal- 

 iculatum (Eigsti, 1941) (Fig. 

 115C). Further, Gerassimova 

 (1933) saw two, three, and even 

 five pairs of sperms in the em- 

 bryo sacs of Crepis capillaris 

 and considers it probable that 

 Fig. 115. Pollen grain and pollen tubes in they originated through addi- 

 Polygonatumcanaliculatum. A, mature pol- tional divis i ons f the or i g i na l 

 len gram, showing vegetative nucleus and mirofsDerms Warmke (1943) 

 two sperms. B, pollen tube, showing elon- K . v ' 



gated vegetative nucleus and two sperms. saw ei ght sperms in an em- 

 C, portion of pollen tube, showing four Dr y° sac of Taraxacum kok- 

 sperms. {After Eigsti, 19 %1.) saghys, and in another there 



