958 PATAGONIAN EXPEDITIONS: BOTANY. 



but they have their own fades; and the presence of any of them at 

 once identifies the source of a collection. Of these the most noteworthy 

 are the species of Ephedm, Chusquea (Gramineae), the Tussock-grass, 

 and Carex patagonica, and species of Uncinia, Philesia and Lapa- 

 geria (shrubs both of Liliaceae), Chlorcea (Orchidaceae), Myzodendron, 

 lodina and Arjona (both of Santalaceae), Hamadryas (Ranunculaceae), 

 Drimys (the celebrated Winter' s-green, of Magnoliaceae), Anarthrophyl- 

 lum and Patagonium (both of Leguminosae, the Patagonium having many 

 species), Accena (Rosaceae, many species), Azorella (Umbelliferae, many 

 species), Schinus (Anacardiaceae, the Incense-bush), Pernettya (Ericaceae), 

 some peculiar species of Verbena, and of Berberis, Benthamiella (Solana- 

 ceae), Boopis and Acicarpha (both of Calyceraceae), Lepidophyllum, 

 Nardophyllum, and many other forms of fruticose Compositae ; many 

 species of Nassauvia and also of Perezia, representing the Mutisieae, a tribe 

 of Compositae. This is a long list of very peculiar and interesting species 

 or genera ; most of which seem to be in or near their primeval homes, 

 and are like the survivors of the inhabitants of a more extensive land. 



The general outcome of the data favors the theory of an incomplete 

 continuity of the southern lands in former times, so as to secure oppor- 

 tunities of transit, and also a measure of relative isolation. The landward 

 side secures some isolation at one part by difference of climate and by 

 impassable plains ; at another by the mountain chain which makes simul- 

 taneously a highway and a barrier. The geological data, as given else- 

 where in these reports, indicate the curious and significant structure of the 

 southern mountains, dividing into parallel ridges, and cross-hatched by 

 deep valleys, and rivers, and gradually sinking southward as well as 

 spreading out like a fan, until they are ultimately lost in the deep ocean, 

 here and there a "rudiment " of former land emerging to betray their secret. 

 A recent writer in Nature summarizes Sir Martin Conway's description of 

 Tierra del Fuego, showing how the deeper hollows between the cordil- 

 leras have been invaded by the sea, so that there is a long trough parallel 

 to the coast-line, and many a transverse channel. And he specially notes 

 the rapid change of sea-level now going on. In Darwin's time the 

 glaciers of Mount Sarmiento reached the sea; now they are separated 

 from the sea by woody belts ; and raised beaches and boulders give evi- 

 dence of frequent oscillating of sea-level. 



Southwards of this system of long fiords and cross-channels, the land 



