THE MALE GAMETOPHYTE 161 



presence of a vacuome and mitochondria in the generative as well 

 as the sperm cells of Narcissus, Asclepias, Vinca, Crinum, and 

 Lilium. Mention may also be made of the "colored bodies" de- 

 scribed by Kostriukova (19396) in living pollen tubes of Lilium 

 martagon. He saw two structures of a pale greenish color, one at 

 each end of the generative nucleus. In older stages these bodies were 

 found to divide and occupy similar positions in the sperm cells 

 (Fig. 100). They were not recognizable in fixed material, but in 

 their places small areolae were seen which stained black with osmic 

 acid. The author concludes that they probably correspond with 

 the structures described as Golgi bodies, but a further study is of 

 course necessary to confirm this. 3 



Regarding the contents of the vegetative cell, starch and fat are 

 the most conspicuous substances. The distinction between starchy 

 and fatty pollen has been recognized for a long time and their pos- 

 sible ecological significance has been a subject of much interest (see 

 Tischler, 1917; Kuhlwein, 1937). Luxemburg (1927) traced the 

 origin of the starch grains and fat bodies from plastids in the pollen 

 grains of several members of the Malvaceae, and believes that the 



3 In his book "The Cytoplasm of the Plant Cell" Guilliermond (1941) remarks 

 that "there is no Golgi apparatus in plants" and that all formations described as 

 Golgi apparatus are elements belonging either to the vacuolar system or to the 

 chondriome. 



Fig. 99. Pollen grains of various angiosperms. A, Cuscuta epithymum, mature 

 pollen grain, showing vegetative nucleus and two male cells. B, pollen grain, 

 showing two vegetative nuclei and dividing generative nucleus. C, vegetative 

 nucleus and three sperms. D, two vegetative nuclei. E, vegetative nucleus, 

 two sperms, and prothallial cell. F, microspore has divided into two parts, of 

 which one on right shows vegetative as well as generative nucleus. (After Fedort- 

 schuk, 1931.) G, Atriplex hymenelytra, pollen grain showing prothallial cell (?), 

 vegetative nucleus, and two male nuclei. (After Billings, 1934.) H, Podostemon 

 subulatus, double pollen grain. /, older stage, in which microspore nucleus of 

 each has divided to form vegetative and generative nuclei; small bodies outside 

 nuclei are starch grains. /, partition wall between the two cells, showing pits. 

 (After Magnus, 1913.) K, Vinca herbacea, dumbbell-shaped pollen grain with 

 two pairs of sperm cells and two vegetative nuclei. (After Finn, 192S.) L, 

 Erythronium americanum, pollen grain, showing vegetative and generative cells. 

 M, same, showing amoeboid nature of generative cell. (After Schaffner, 1901.) 

 N, Wormia suffruticosa, pollen grain, showing large crystal. (After Paetow, 1931.) 

 0, Lupinus luteus, pollen grain, showing chloroplasts in generative cell as seen after 

 silver impregnation. (Ruhland and Wetzel, 1924.) 



