88 



The rudimentary intermedian envelop in the incomplete 

 female flowers is seen in fig. 14 PI. Ill, while the only existing 

 envelop of the male flower is pictured in fig. 15 PL HI. A 

 longitudinal very thick section of the female flower shows that 

 the integument is irregularly lobed at the top (fig. 16 PI. Ill)' 

 a fact which is seen better yet on a surface view after peeling 

 off of the external envelop (fig. 17. PL III). This internal en- 

 velop grows out to a long tube projecting considerably above 

 the outer envelops and functionating as a stigma as is seen 

 in fig. 18 PL III, on longitudinal section, and in fig. 6 as well 

 as at a fig. 4 PL II, on external view. We may therefore speak 

 of an integumental stigma. 



It is thus seen that the floral envelops really arise in the 

 manner stated by former investigators so that the only question- 

 nable point is the morphological value to be attributed to the 

 difi'erent parts. 



To my mind the views of Beccari and Strasburger who con- 

 sider the whole flower of Gnetum as an adventitious bud are 

 doubtless correct, consequently the morphological value of the 

 different envelops only needs to be discussed. 



Blume considered the external envelop as an ovary containing 

 an ovule with two integuments. Hooker says nothing as to the 

 morphological nature of the envelops but states that the inner 

 envelop never contains vascular tissue while the two outer 

 ones do. Strasburgeb considers all three of them to be of the 

 nature of integuments, the two inner ones he claims to be 

 homologous to the one internal integument of Ephedra, the 

 outer one to the external integument of Ephedra. 



Beccari considers the tip of the axis as a naked ovule, the 

 internal envelop as an ovary, the intermedian envelop as the 

 homologon of the staminal whirl of Welwitschia and the exter- 

 nal envelop as a perianth. This view of Beccari seems to me 

 to be of little value as the differences between the male flowers 

 of Welwitschia and those of Gnetum are so large that it would 

 be exceedingly hazardous to compare them and where even 

 the stamen of Welwitschia is not at once comparable to the 



