538 REPORT—1883. 
removed. According to Miiller the most frequent visitor to Reseda is the bee 
Prosopis, which has a flat trowel-shaped proboscis which it uses in plastering its 
cell. 
The nectar gland of Reseda bears such an obvious correlation to this form 
of proboscis as to favour the conclusion that in Reseda we have a flower specialised 
for crossfertilisation by short-lipped bees. The slender filiform proboscis of the 
honey-bee or butterfly is manifestly correlated to deep tubular flowers like Phlox 
or Honeysuckle, but does not correspond to a nectary like that of Reseda. On the 
principle that an oyster is more easily opened with a trowel than with a needle, we 
may regard the box-like nectary of Reseda as corresponding to the short flat 
proboscis of Prosopis. This points to the probability of Reseda being a very 
ancient type of flower, since the short-lipped bees belong to an earlier and more 
generalised type of insect than the specialised honey-gatherers. The condition in 
the flowers ot Reseda is almost the reverse of what we find in the buttercup. 
In the latter the honey is contained in a little hollow in the petal, and is roofed 
over by the scale. In Reseda the position of the flower is changed—the scale is 
hollow and holds the honey, while the petal forms the roof of the nectary. 
The scale of Ranunculus and the disk of Reseda are not homologous, and the 
comparison is only in regard to function, From the examination of the flowers 
of Reseda from this point of view, we are led to regard them as exhibiting a 
higher degree of specialisation in relation to insects than has hitherto been sus- 
pected. At the same time we see that in them the adaptation is not, as it is in the 
majority of flowers, most apparent in the calyx, corolla, or stamens, but in the 
peculiar development of the disk. 
7. On the Closed Condition of the Seed-vessel in Angiosperms. 
By Professor ALEXANDER S. Witson, M.A., B.Sc. 
Flowering plants may be divided into two classes, according as their seeds 
are contained within a closed seed-vessel, or are exposed without any such 
covering. ‘The former, having their seeds included in a pod or pistil, are called 
Angiosperms or cover-seeded; and the latter, on account of their naked seeds, 
Gymnosperms. The Angiosperms, which form by far the more important 
division, embrace most of the common plants which make up the bulk of our 
flora, and are universally regarded as the more highly organised of the two. 
Corresponding to the lower degree of organisation, G-ymnosperms (yew, cypress, 
fir, &c.) appear earlier in the geological strata, and are largely represented in a fossil 
state. The pod of an Angiosperm, such as that of a wall-flower, is composed of 
metamorphosed leaves termed carpels. In nearly every instance these leaves are 
so united as to form a completely closed case enveloping the young seeds, At 
first sight it would seem as if the presence of such a covering were a disadvantage, 
for before the young seeds or ovules can develop to maturity they require to be 
fertilised. The process of fertilisation is effected by the agency of pollen-dust 
which is brought to the flower either by the wind, or by insects visiting the 
flower in search of honey. Now in the case of Gymnosperms, where the seeds are 
exposed uncovered, this pollen-dust if blown by the wind simply alights on the 
surface of the seed and fertilises it directly. In plants with covered seeds, on the 
other hand, the pollen cannot gain direct access to the ovules, but can only fall on 
the surface of the envelope formed by the carpellary leaves. This covering has to 
be penetrated before fertilisation of the seeds can be effected. For this purpose 
several adaptations of tissues, modifications of structures, and changes in the 
position of the ovules are rendered necessary, all of which might easily be dis- 
pensed with were the seeds exposed as they are in Gymnosperms. It can hardly be 
supposed that all this specialisation, whereby the process of fertilisation so simply 
performed in Gymmnosperms becomes complicated by being broken up into 
numerous subsidiary processes, should be called into play unless some very impor- 
tant end were to be attained by the presence of a completely closed pistil. What 
then is the réle of the pistil? The young seeds are the most vital parts of the 
‘vegetable organism. Composed of delicate cells, containing much nitrogen and 
