140 Miscellaneous. 



ceous bird, but the lower mandible still stronger ; the lower fourth 

 of the bill is enveloped in a curious horny sheath, quite unlike any 

 other bird I am acquainted with. A curious naked caruncled skin 

 surrounds the eye, and similar caruncles are situated under and be- 

 fore the eye. I have no work containing any detailed description 

 of the only species known of this genus, except Cuvier's short 

 notice, but so far as it goes that agrees with my bird. Darwin does 

 not notice it as a native of the Falklands, and had he seen it, it is 

 not likely he would have omitted such a remarkably anomalous bird. 

 I know not if it was brought home by the ' Erebus' and ' Terror' ; the 

 bird is not unfrequent in flocks on the sea-shore. I dissected seve- 

 ral specimens ; all had their large crops filled with a small white 

 nereidous annelide : the strong bill would seem to point to a still 

 more truly conchivorous diet than its near allies the oyster- catchers, 

 yet this does not seem to be the fact. The Chionis appears to form 

 a Rasorial type in the Grallatorial circle. 



Two true oyster-catchers are not uncommon, one black and white 

 very like our British species, and the other brown and larger. A 

 dottrel very similar to our ring dottrel and a small gray tringa are 

 common, and on the moors a large snipe is frequent, and furnished 

 some of our sportsmen with very good shooting. 



As regards the geology I have little to communicate : all the di- 

 strict which I visited is composed of a dull gray quartz rock more or 

 less distinctly stratified, and frequently, when good sections are to 

 be seen, which are by no means common, exhibiting very remark- 

 able flexures and contortions, similar to those which are so common 

 in the Northern Islands in gneiss and mica slate. There is also 

 sandstone in the islands, supposed to belong to the Silurian period, 

 but none within a day's journey of us, and I consequently did not 

 see it.. Darwin mentions the remarkable " streams of stones" found 

 in these islands. I shall give you the results of a careful examina- 

 tion of several of them. 



The " stream " consists of a mass of angular blocks of quartz, va- 

 rying in size from a man's head up to that of a small house, but 

 averaging about four or five cubic feet ; they generally occupy a flat 

 valley, and the inclination is mostly very little, in none which I saw 

 exceeding 10° or 12° ; they vary in extent, but are generally one to 

 three miles long. For the most part the stones forming the stream 

 are piled one on the top of the other to a considerable depth in the 

 soil, as no vegetation is to be seen in the crevices ; the stones are 

 covered by lichens, and show no marks of attrition by water, being 

 on the contrary always somewhat angular. I cannot venture to pro- 

 pose any theory regarding these curious appearances. Mr. Darwin, 

 whose observations are always as accurate as his conclusions are 

 cautious and rational, suggests (though apparently rather as a " si- 

 mile" than a theory) that the effect is similar to what would happen 

 if a stream of lava had been suddenly rent into fragments by some 

 violent internal convulsion; and the simile is very just, though we 

 cannot for a moment suppose that quartz rock has flowed over a 



