THE MEGASPORANGIUM 



49 



without an integument, in which there are several archesporia. 

 Hofmeister favored the latter view, while Treub inclined to the 

 former, as his explanation of it as a fusion of rudimentary 

 ovules and placentas would seem to indicate. In 1883 Treub 19 

 discovered exactly the same structure in Loranthus pentandrus. 

 In 1895 the same investigator 29 described Balanophora elon- 

 gaia as having no ovule or placenta. In 1896 this was con- 

 firmed by Van Tieghem 34 for B. indica ; and in 1899 by 

 Lotsy 48 for B. globosa (Fig. 17). Lotsy claims that in B. 

 globosa there are no flowers, carpels, placenta, or ovules; but 

 that a hypodermal cell in a protuberance of the floral axis gives 

 rise to the embryo-sac, while 

 the epidermal cells over it de- 

 velop a long, style-like organ 

 resembling the neck of an 

 archegonium. Hofmeister de- 

 scribes and figures the pollen- 

 tube of B. polyandra as grow- 

 ing down into this " stylar 

 canal," as he called it (Fig. 

 16, C y ). It would appear from 

 the figures that the " protu- 

 berance of the floral axis " is 

 a megasporangium without in- 

 teguments, and that the so- 

 called " style " is a remarkable 

 outgrowth of the nucellus. 

 The pollen-grains, as figured 

 by Hofmeister, therefore, come 

 in contact with the nucellus, 

 as in Gymnosperms. In this 

 connection attention may be 

 called to the remarkable beak 

 developed by the nucellus of 

 Euphorbia corollata as de- 

 scribed by Miss Lyon 41 (Fig. 

 18), a beak which suggests the same general tendency of the nu- 

 cellus which has reached such an extreme expression in Balano- 

 phora. The investigation of Rhopalocnemis phaUoides (Balano- 

 phoraceae) by Lotsy, 52 however, as well as the case of Balano- 



FIG. 18. Euphorbia corollata. Longitudi- 

 nal section showing an excessive pro- 

 longation of the nucellus; x 650. After 

 LYON. 



