Soils and Soil-formers.] SUB ANTARCTIC ISLANDS OF NEW ZEALAND. 751 



Muntz and Girard (35) have patented a method of obtaining ammonia and 

 nitrates from peat by means of superheated steam. Were this Dominion cut off 

 from supplies of nitre, as France once was, humus soils so rich in nitrogen might 

 prove the only immediately available source of nitre for making gunpowder. 



It is somewhat remarkable that, as far as can be ascertained, all southerly 

 stations ravaged by salt-laden gales produce humus soils without the aid of mosses. 

 Darwin (43) speaks of the Falkland Islands* as an undulating land with a desolate 

 and wretched aspect, everywhere covered with peaty soil and wiry grass of one 

 monotonous brown colour. The Falkland Islands country rock is clay, slate, and 

 sandstone. 



Speaking of the Chonos Archipelago, Darwin (43) says, " Every patch of level 

 ground is covered with two species of plants, Astelia pumila and Donntia magellanica, 

 which by their joint decay compose a thick bed of elastic peat. In Tierra del Fuego, 

 above the region of woodland, the former of these eminently sociable plants is the 

 chief agent in the production of peat. Fresh leaves are always succeeding one to 

 the other round the centre tap-root, the lower ones soon decay, and in tracing 

 a root downwards in the peat the leaves yet holding their places can be observed 

 passing through every stage, until the whole becomes blended in one confused 

 mass." 



Astelia is assisted by Myrtus nummularia, Empetrum rubrum, Juncus grandi- 

 florus — plants possessing a close general resemblance to the English species of the 

 same genera. The climate of the southern part of America appears particularly 

 favourable to the production of peat. In the Falkland Islands even the coarse 

 grass which covers the whole surface of the land becomes converted into this sub- 

 stance ; scarcely any situation checks its growth. Some of the beds are as much 

 as 12 ft. thick, and the lower part becomes so solid when dry that it will hardly 

 burn. Although every plant lends its aid, yet in most places the Astelia is the most 

 efficient. 



It is rather a singular circumstance, as being so different from what occurs in 

 Europe, that Darwin nowhere saw moss forming, by its decay, any portion of the 

 peat in South America. This is so significant, and illustrates so exactly what is 

 taking place in many parts of the subantarctic islands that I reproduce his views 

 here. 



The " Challenger " Eeports (vol. ii, p. 888) describe the Falkland Islands as a 

 treeless expanse of moorland bog and bare and barren rock. Bolax gleharia forms 

 " balsam bogs," the plant simulating in appearance the elastic cushions of Azorella 

 Selago at Kergulen Island, another peat-ridden country. 



The Falkland Islands are in the same latitude as London and Campbell Island, 

 and are subject to thick fogs. Dangerous overflows of peat bogs, or " bog-slides," 

 have occurred at the Falkland Islands (44). A curious effect of the peaty soil on 

 the feet of animals is noted in the " Challenger " Reports : the hoofs of horses 



* The common grass there is a species of Dactylis, a sister species to the cocksfoot (Dactylis glo- 

 merata). This forms tussocks in the same way as the Danthonia and Poas do in the Auckland Islands. 

 The fact that the Falklands are noted for their cattle-raising industry suggests that the grasses of those 

 islands might with advantage be tried on the soils of the Auckland and Campbell Islands, where the 

 indigenous grasses are rapidly being eaten out by stock. Mutual exchange of the grass-seed of these 

 islands might benefit both. 



