370 Mr John Wilson on the Fertilisation of Albuca. 



the depression, which is bounded by the exterior faces of 

 the deflexed apices of the inner perianth segments. As 

 in the other species, the knob, and the portions of the 

 segments in juxtaposition with it, are clothed with papillae. 

 In A. corymbosa the incurved apices referred to are tri- 

 angular, tapering, and hook-like ; in ^ . Juncifolia they 

 form a semicircular pad of relatively great thickness in the 

 middle, and thin and flexible at the junction with the main 

 body of the segment. The outer stamens are quite anther- 

 less. The flowers are more odorous than those of A. corym- 

 bosa, and the nectary occupies a much smaller area, being 

 perhaps confined to the narrow space between the base of 

 the filament and the ovary. The filaments are the same 

 in both species. The structural characteristics of A. junci- 

 folia indicate that it is more highly specialised than A. 

 corymbosa; and the following details of the experiments 

 tend to substantiate the belief that it is also as highly, if 

 not more highly, adapted to cross-fertilisation. The nine 

 flowers forming the panicle were thus dealt with: — 



1st flower removed (eventnally). 



2nd „ impregnated with pollen from the 1st. 



3rd „ impregnated with pollen from the 4th. 



4th. „ unimpregnated. 



5th ,, impregnated with own pollen. 



6th ,, impregnated "with pollen from the 5th on the 



jDrotruding tip of the stigma. 

 7th ,, impregnated with own pollen after the flower 



had been four days open. 

 8th „ impregnated with own pollen. 

 9th „ removed. 



In no instance did fertilisation take place. 



EXPLAXATIOX OF PLATE XII. 

 Albuca corymbosa. 



Fig. 1. Albuca corymbosa in flower (reduced). 



Fig. 2. A single flower, having an outer perianth segment bent down- 

 ward (nat. size), os, outer perianth segment; is, inner 

 perianth segment ; ost, outer stamen ; jy, apical pad. 



Fig. 3, A single flower, having an inner perianth segment bent 

 downward (nat. size). Eeferences as in fig. 2. 



Fig. 4. An inner segment, with inner stamen in situ, pa, papillose 

 area ; spr, spring. 



Fig. 5. Pistil, pr, stigmatic prominence ; gl, septal gland. 



Fig. 6. Stigma, ^r, stigmatic prominence. 



Fig. 7. Transverse sections of a leaf, a, at the base ; b and c, near 

 the apex. 



