1886-87.] the Flowers of Wachendorfia paniculata. 77 



have been made with the flowers of a single vigorous inflor- 

 escence. Of the forty-three flowers borne by it (all as visual 

 of one type), six were untouched, twenty fecundated with 

 their own pollen, and seventeen with pollen from a different 

 flower. Although done in the most favourable circumstances, 

 and the pollen applied in many ways, — for instance, from 

 nearer or more remote flowers, from the one or the other of 

 all three stamens, — no seed at all was borne. Such a result 

 goes to emphasise the significance of the figures in the last 

 two columns of the second table, strengthening the assump- 

 tion that the dimorphism of the flowers is of decided benefit 

 to the species.] 



Explanation of Plate I. 

 Wachendorfia paniculata. 



Fig. 1. Wachendorfia panicidata {vedi\\Q.(idi). //, lowest flower. 

 Fig. 2. Front view of a single flower (nat. size), us, upper outer 



segment of the perianth ; Is, lower inner segment ; sty, 



style ; s, stamen corresponding to the style ; o, aperture 



of passage to honey-gland. 

 Fig. 3. Front view of the opposite type of the flower depicted in 



fig. 2 (nat. size). 

 Fig. 4. Side view of a flower (nat. size), gl, honey-gland bearing 



a drop of nectar. 

 Fig. 5. Front view of the ovary (nat. size), sty, base of style ; st, 



base of stamen ; gl, honey-gland. 

 Fig. 6. Side view of reproductive organs (nat. size), hs, base of 



upper stamen. 



On the Fructification of Sphacelaria radicans, Harvey, and 

 Sphacelaria olivacea, J. Ag. By G. W. Traill, 

 Joppa. (Plate II.) 



(Read 10th February 1887.) 



These plants differ greatly, both in general appearance 

 when growing, and also in their fructification ; yet, owing to 

 their similarity of structure when viewed under the micro- 

 scope, they have generally been considered by authors as 

 belonging to one species. Both occur on sandstone rocks at 

 many places along the shores of the Firth of Forth, but at 

 very different levels. 



The one, S})hacelaria radicans of Harvey's Phycologia 



