74 BULLETIN OF THE 
canoes of the mainland, the latter consisting of trachytic and andesite 
material, while the former are made up of basaltic rocks. The speci- 
mens of volcanic rocks which I collected at Chatham Island, on Charles, 
and on Duncan Island, were all basaltic. 
Wolf, whose acquaintance with the flora of the high Andes appears to 
be very extensive, was struck with the Andean character of the Compos- 
ite, and with the analogy of a species of Polylepis and other trees with 
those forms that in the high Andes! make small forests, reaching to an 
altitude of 13,000 feet. He found also a remarkable similarity in the 
mosses and ferns with those of the Quito district, and some of the species 
he even considers as identical? As he well says: “ Es ist kein Zweifel, 
dass die Vegetation, trotz ihrer Eigenthümlichkeiten, im Ganzen einen 
südamerikanischen Typus besitzt, sowohl nach den Gattungen als nach 
dem äussern Habitus; wodurch sie sich aber auf den ersten Blick von 
der Flora des Festlandes auch dem Nicht-Botaniker unterscheidet, ist 
die Kleinheit der Blattorgane? die Abwesenheit schöner Dlüthen, die 
Seltenheit der epiphytischen Gewächse, und das Fehlen der Lianen oder 
Schlingpflanzen.” We miss all the wealth of the tropical forests, which 
is so striking in the equatorial zone of Central and South America. 
Tue Deep-Sea Fauna or toe Panamic District. 
Asa striking result of the character of the deep-sea fauna of the 
Panamic district, we found, in the first place, a great many of my old 
West Indian friends. In nearly all the groups of marine forms among 
1 Is it not perhaps more natural to compare the vegetation of the lower belt of 
the Galapagos to that of the rainless belt extending along the coast of South Amer- 
ica from Ecuador southward? The stunted character of the vegetation of the rain- 
less belt is as marked a feature of that district as it is of the Alpine regions. 
2 Hooker, while discussing (Trans. Lin. Soc., 1851, Vol. XX. p. 163) the affinities 
of the flora of the Galapagos and its origin, Jays great stress upon the action of 
currents coming north from the Guyaquil River, and those flowing westward from 
the Bay of Panama, as agents for the distribution of South and Central American 
plants. Speaking of the affinities of the plants of the Galapagos, he says: “The 
new species being for the most part allied to plants of the cooler parts of America, or 
the uplands of the tropical latitudes. The more peculiar aie the same as abound 
chiefly in the hot and damper regions, as the West Indian Islands and the shores of 
the Gulf of Mexico.” 
8 As Darwin says, the bush which from its minute brown leaves chiefly gives 
the leafless appearance to the brushwood is one of the Euphorbiacew, and an acacia 
and a cactus are quite common in some parts, while in the upper regions of the 
islands the ferns and coarse grasses are abundant. 
