1881.] on Fruits and Seeds, 597 



that he never could understand what was the use of the teeth on the 

 capsules of mosses. " Oh," replied his friend, " I see no difficulty in 

 that, because if it were not for the teeth, how could we distinguish 

 the species '? " We may, however, no doubt, safely consider that the 

 peculiarities of seeds have reference to the plant itself, and not to the 

 convenience of botanists. 



In the first place, then, during growth, seeds in many cases 

 require protection. This is especially the case with those of an 

 albuminous character. It is curious that so many of those which 

 are luscious when ripe, as the Peach, Strawbeiry, Cherry, Apple, 

 &c., are stringy, and almost inetliblc, till ripe. Moreover, in these 

 cases, the fleshy portion is not the seed itself, but only the enve- 

 lope, so that even if the sweet part is eaten the seed itself remains 

 uninjured. 



On the other hand, such seeds as the Hazel, Beech, Spanish Chest- 

 nut, and innumerable others, are protected by a thick, impervious 

 shell, which is especially developed in many Proteaccfc, the Brazil- 

 nut, the so-called Monkey-pot, the Cocoa-nut, and other palms. 



In other cases the envelopes protect the seeds, not only by their 

 thickness and toughness, but also by their bitter taste, as, for instance, 

 in the Walnut. The genus Mucuna, one of the Leguminosae, is 

 remarkable in having the pods covered with stinging hairs. 



In many cases ripening of the seed is accompanied by important 

 movements of the neighbouring organs. In some, for instance, the 

 calyx, which is closed when the flower is in bud, opens when the flower 

 expands, and then, after the petals have fallen, closes again until the 

 seeds are ripe, when it opens for the second time. This is the case 

 with the common Herb Eobert [Geranium rohertianum). In Atractylis 

 cancellata, a South European plant, allied to the thistles, the outer 

 envelopes form an exquisite little cage. Another case, perhaps, is 

 that of Nigclla, the " Devil-in-a-busli," or, as it is sometimes more 

 prettily called, " Love-in-a-mist," of old English gardens. 



Again, the jirotection of the seed is in many cases attained by 

 curious movements of the plant itself. In fact, plants move much 

 more than is generally supposed. So far from being motionless, they 

 may almost be said to be in perpetual movement, though the changes 

 of position are generally so slow that they do not attract attention. 

 This is not, however, always the case. We are all familiar with the 

 Sensitive Plant, which droops its leaves when touched. Another 

 species (Averrhoa hilimhi) has leaves like those of an Acacia, and all 

 day the leaflets go slowly up and down. Dcsmodiuia gyrans, a sort of 

 pea living in India, has trifoliate leaves, the lateral leaflets being 

 small and narrow ; and these leaflets, as was first observed by Lady 

 Monson, are perpetually moving round and round, whence the specific 

 name gyrans. In these two cases the object of the movement is quite 

 unknown to us. In Dioncea, on the other hand, the leaves form a 

 regular fly-trap. Directly an insect alights on them they shut up 

 with a snap. 



2 T 2 



