311 



IX. Notes on the Morphology of certain Structures concerned in Rept^oduction in the 



Genus Gnetum *. By H. H. W. Peaeson, Sc.D., F.L.S., Henry Bolus Brofessor 

 of Botany in the South African College. 



(Plates 31, 32.) 



Read 4tli June, 1914 



g is an account of an investigation of material already described f 



The foiio^\ 



together with further supplies J, for which I am indebted to 



1. Mr. J. Gossweiler {Gnetum africanum). 



A. Collected at Montobello, Angola, in February 1912. 



B. Prom the same locality, collected in December 1912. 



2. Dr, B;. H. Lock {Gnetum Gnemon). 



\ 



C. Collected in Ceylon. 



D. Collected in Ceylon on various dates between August 5 and October 27, 1912. 



3. Mr. I. H. Burkill. 



r 



E.' Collected in. Singapore, August 1913. 



In all these cases the ovules and male spikes were carefully fixed in various 

 fixatives— weak Plemming's solution, alcohol formalin, mercuric chloride solution, and 

 chromo-acetic acid. While the fixation was usually successful, delicate structures " 

 frequently suffered to some extent in transmission 



Consequently the free-nuclear 



of the embryo-sac are somewhat contracted, and no trustworthy information regardin 

 the structures in the pollen-tube and fertilization has yet been obtained 



Stases in the 



development of the pro-embryo and embryo have been figured, but their pubUcat 

 postponed untU the account can be made more complete. 



A. The Spike and the Pemale Plowee. {G. Gnemon) 

 Most writers have hitherto referred to only two forms of spike in Gnetum, viz. :— 



1. The pure female spike bearing ovules, each with three envelopes. Many of 



these are normally arrested ; the rest are fertile. 



2. The pseudo-androgynous (a male) spike, bearing functional male flowers and 



infertile ovules with two envelopes only 



•West 



the Eoyal Society), 



Report No. 22, 

 t Pearson, 1912. 



-♦• 



Material of G. scandem, recently sent from Darjeeling by ilr. G. H. Cave, awaits investigation. 



SECOND SERIES. — BOTANY, VOL. VIII. 



2 



