'I'liK i)jsri:i;sAL of st<:ei)S. 
117 
be anticipated, not very usual for the seed itself to be fleshy, as it is in 
Iris fa'tidissinia, though it is frequently bright-coloured iind variously 
inarked, so as to attract birds, in which case every seed will not pro- 
bably be crushed in the gi/zard. It must be remembei'ed that fruit- 
eating birds have not the same muscular gizzards that characterise the 
seed-eaters, whilst one of the most general characteristics of seed — I 
hesitate to term it an adaptation — is the imperviousness of the bitter 
leathery testa to the action of the gastric juices. It is worthy of men- 
tion that gaily coloured seeds, such as those of many Leguminosre, are 
confined to dehiscent fruits ; and that fleshy, brightly coloured "arils," 
such as the mace of the Nutmegs (Myristica), the cup of the Yew berry, 
and the scarlet coat of the Spindle-tree, Tennyson's 
Fruit that in our autumn woodlands looks a flower, 
are more frequent than fleshy seeds. In Acacia homalopliylla a long 
red funicle, or seed-stalk, serves as the attraction, and in the Juniper the 
berry " is strictly a simplified cone with fleshy scales. Far more 
numerous, however, and more varied, are the instances of succulent 
fruits. Though what is technically known as a " berry " or a " nuculane " 
occurs in a number of unrelated orders (as, for example, the Gooseberry, 
the Prickly-pear, and the Banana in the former case, and the Grape and 
the Tomato in the latter), it is important to note that some other suc- 
culent types of fruit, such as the "drupe" and the "pome" are 
characteristic of extensive, varied, widespread, and, therefore, geologi- 
cally ancient sub-orders. I need not, I am sure, point out to you that 
here again, as in the cases of wings, parachutes, or hooks, structures 
which are so far physiologically similar as to be alike succulent, are of 
very different origins. Most of the flesh of a Gooseberry, for instance, is 
the testa of the seeds ; that of a Cherry is mesocarp, i.e. the mesophyll of 
the carpellary leaf ; that of the Apple is receptacular in origin ; and that 
of an Orange an outgrowth from the endocarp, or inner layer of the ovary. 
Succulence, therefore, has originated along various independent lines. 
In addition to those succulent structures, there are, how^ever, a few 
imperfectly understood cases of what seem to be adaptations for what I 
have termed inside carriage by animals. These are cases in which seeds 
or fruits resemble insects or allied animals. The seeds of Ahrus, 
AclenantJicra, Jatropha, and Bicinus resemble beetles, the suggested 
explanation of the use of this resemblance being that birds may carry off 
these seeds by mistake, and so aid in their dispersal. The seeds of the 
Cow-wheat (Melampyrum) resemble the cocoons of ants so closely that, 
as Lundstrom has observed, ants do actually carry them to their nests, 
where presumably the plant benefits by being able to germinate in the 
fine tilth of an ant-hill. The pod of the leguminous Scorpiuriis 
suhvillosa closely resembles a centipede, and that of S. veriniculata is 
equally like a caterpillar ; but perhaps the most remarkable of these 
cases is that of the common Marigold (Calendula officinalis, L.), in which 
— sometimes apparently in one flower-head — three types of fruit occur, 
viz. one with longitudinal flanges . or wings that might aid its dispersal 
by wind, another in which these flanges consist mainly of somewhat 
hooked projections which would catch in the hides of passing animals, 
and a third which remarkably resembles a green caterpillar. 
