27 



" Rhizophora, Avicennia and Sccevola. — These all have a predilec- 

 tion for salt water, and constitutional power in the embryo of 

 resisting its destructive effects. Scaevola has a hard putamen 

 and scanty carnose albumen ; the other species are exalbu- 

 minous. 



" Apocyneee. — Vallesia I believe to be a salt-marsh or sea-side plant; 

 it has a scanty albumen. 



" ConvolvulaceoB. — These have a scanty mucilaginous albumen. 

 Two of them, Ipomsea maritima and Calystegia Soldanella, 

 are sea-side species, with particularly wide ranges. 



" Solanece. — Small seeds and adhesive glands of Nicotiana gluti- 

 nosa ; indurated osseous testa of Dictyocalyx, Solanum and 

 Lycopersicum. 



" Verbenaceea. — Exalbuminous embryo and osseous endocarp of 

 Clerodendron and Lantana. 



" Labiatce, Cordiacece and Boraginea. — Nucumentaceous pericarps 

 and very scanty albumen. Cordia and Boragineae are exal- 

 buminous. 



" Acanthacece. — Exalbuminous hooked seeds. 



" Planlaginece. — Very dense corneous albumen. 



" Plumbaginece, and Plantaginea. — Viscid glands on calyx, and 

 hooked prickles of some Pisoniae. 



" Euphorbiacece and Urticea. — Non-peculiar species of these may 

 have been introduced through the agency of man into Charles 

 Island. 



" Hypoxidece and Commelinece offer no apparent facilities for the 

 extraordinary range of the two species that represent these 

 orders. 



" Cyperacea. — These have some facilities for adhesion to foreign 

 substances, and the firm nature of the pericarp, further covered 

 by the coalescing scales of the perianth, are protections. 



" Gramineoe. — The ciliated glumes of Poa ciliaris and the awns of 

 Setaria Rottleri are the only very evident aids to migration 

 which I can adduce. The resistance of the seed to the ac- 

 tion of salt water must be very slight indeed. 



" Cryptogamia. — The excessive minuteness of the sporules in this 

 great class, together with the sporadic appearance of these 

 where they are most minute, and the sudden development of 

 others in suitable situations, leave little doubt that their dif- 

 fusion by the winds is a never-ceasing though invisible ope- 

 ration. 



