370 report — 1879. 



5. Report of the Committee on the Zoological Station at Naples. — 



See Reports, p. 165. 



6. Report of the Committee for investigating the Natural History of 

 Socotra. — See Reports, p. 210. 



FRIDA T, A UG USX 22. 



The following Papers were read : — 



1. On Fruits and Seeds. 

 By Sir John Lubbock, Bart., V.P.R.S., M.P., D.C.L., LL.D. 



Sir John commenced by calling attention to the difference presented by seeds, 

 some being large, some small, some covered with hooks, some provided with hairs, 

 some smooth, some sticky, &c, and after observing that there were reasons for all 

 these peculiarities, proceeded to attempt to explain some of the more striking. In 

 the first place, he said, many seeds required protection from birds and insects. 

 Hence the shells or husks of the beech, Spanish chestnut, horse chestnut, walnut, 

 &c. In some cases, as in the common Herb Robert, the calyx or outer envelope of 

 the flower opens when the flower expands, closes over the seeds when the flower 

 fades, and opens again when the seeds are ripe. In other cases the flower-stalk 

 changes its position. Thus, in the Dandelion, it is upright when the flower is 

 expanded, lies close to the ground after the flower has faded, and rises again when 

 the seeds are ripe. In the Cyclamen, again, the flower-stalk curls itself up into a 

 spiral after the flower has faded, 



He then called attention to the modes of dispersion, by means of which seeds 

 secure a sort of natural rotation of crops, and are also in other cases enabled to 

 rectify their frontiers. Some plants actually throw their seeds. Thus, in the 

 common Cardamine, the outer membrane of the pod becomes very tense, and when 

 ripe, at the least touch it gives way at the base, and curling up with a spring, 

 throws the seeds three or four feet. The common geraniums and A-iolets also throw 

 their seeds, and so do some of the cucumbers ; but in these cases the mechanism is dif- 

 ferent. He then described the curious l elaters ' of the equisetums, and other means of 

 dispersion possessed by seaweeds and other low organised plants. Among the higher 

 plants the seeds are in many cases transported by the wind. Sometimes, indeed, 

 the whole plant is thus blown about, as in the case of the celebrated Rose of 

 Jericho, an annual, inhabiting the sandy plains of Palestine, Syria, and Arabia, 

 which, when dry, curls itself up into a ball, and is thus blown over the surface of 

 the ground till it comes to a damp place, when it uncurls, the pods open and shed 

 their seed. 



Many seeds are provided with a wing which catches the wind and thus aids in 

 dispersion. Such seeds occur, especially on trees, such as the pine, fir, ash, maple, 

 sycamore, hornbeam, and many exotic species. In these cases the seeds are large, 

 but many herbs have small seeds, provided with foliaceous expansions serving the 

 same purpose. These are sometimes so thin as to be transparent, and in Thysano- 

 carpus elegans the membrane is even perforated by a series of holes. In other 

 cases the seeds are provided with hairs, which catch the wind, sometimes forming 

 exquisite fairy parachutes. Such, for instance, are the dandelion, &c; but it is 

 curious that very different parts of the plant are modified into these hairs. Thus 

 in the dandelion and valerian it is the calyx ; in the bulrush, the perianth, in the 

 willow herb, the crown of the seed ; in cotton grass, the base. In the true cotton 

 the whole seed is covered with hairs. Thus, then, although the result is the same, 

 the mode of arriving at it is very different. 



He then proceeded to the cases in which the dispersion of seeds is effected 

 by the agency of animals. In many cases the seed is surrounded by a sweet, 

 fleshy pulp, which is eaten, while the true seeds, being surrounded by a tough 



