420 TJie ''Green Balls" of Loch Kildonan. [Sess. 



nut has been found on the shores of the west coast of Scot- 

 land, transported by ocean currents from the tropics. The 

 fruit of the mahogany tree has been known to perform long 

 voyages without injury to its vitality. The capsule of the 

 sycamore, on becoming detached from the parent tree, falls to 

 the earth with a series of revolving motions similar to the 

 propeller of a steamer, fixing the seed-vessel, with its con- 

 tained seeds, in the earth. In Trifolium subterraneum, the 

 pods burrow in the earth when ripening their seeds, and in 

 that manner make sure of a succession of individuals of their 

 own kind. A peculiar phenomenon of plant multiplication is 

 " mimicry." In some of the pod-bearing tribes the seed- 

 vessels look so exactly like caterpillars that birds are induced 

 to peck at them, and thereby scatter their seeds. A few 

 species of flowering-plants are viviparous — the seeds sprouting 

 within the ovarian cavity, and falling to the ground in every 

 respect the same as the parent. This wonderful provision is 

 obviously both for the propagation and spread of the species, 

 as it is only in alpine and exposed situations that this pro- 

 pensity is developed. Lastly, in several instances plants pro- 

 duce numerous seeds, yet never open their flowers. Lamium 

 amplexicaule and Viola canina are familiar examples. 



It will be seen, from the few scattered examples which I 

 have given — first, that the natural contrivances for the propa- 

 gation and dispersion of plants are nearly as numerous as the 

 plants themselves ; and, second, that we everywhere find cer- 

 tain laws in operation which indicate special adaptations of 

 means to end. 



Y.—TEE "GREEN BALLS" OF LOCH KLLDONAN. 



. By Mr T. B. SPRAGUE, M.A., F.R.S.E. 



{Feb. 25, 1891.) 



Mr T. B. Sprague brought under the notice of the members 

 of the Society several specimens of " green balls " gathered 

 from the bottom of Lower Kildonan Loch, in South Uist. 



