﻿Rev. T. G. Bonney — Formation of Cirques. 273 



Poramhoyiites, KonincMna, and several others, which, made their ap- 

 pearance very suddenly and without any wai-ning ; after a while they 

 disappeared in a similar abrupt manner, having enjoyed a compara- 

 tively short existence. They are all possessed of such marked and 

 distinctive internal characters that we cannot trace between them 

 and associated or synchronous genera any evidence of their being 

 either modifications of one or the other, or of being the result of 

 descent with modification. Therefore, although far from denying 

 the possibility or probability of the correctness of the Darwinian 

 theory, I could not conscientiously affirm that the Brachiopoda, as 

 far as I am at present acquainted with them, would be of much 

 service in proving it. The subject is worthy of the continued and 

 serious attention of every well-intormed man of science. The sublime 

 Creator of the Universe has bestowed on him a thinking mind : there- 

 fore all that can be discovered is legitimate. Science has this ad- 

 vantage, that it is continually on the advance, and is ever ready to 

 correct its errors when fresh light or new discoveries make such 

 necessary. 



The importance of the study of the Brachiopoda must be obvious 

 to all. They are among the first well-known indications of life in 

 this world ; and they have continued to be very extensively repre- 

 sented up to the present time. They are also very characteristic 

 fossils, by which rocks at great distances, whether in New Zealand 

 or Spitzbergen, in the Himalayas or the Andes, can be identified 

 without its being eve-n necessary for the palasontologist to visit the 

 district from whence the fossils are derived. They are, as Mantell 

 would have termed them, sure medals of creation, the date of their 

 appearance firmly stamped upon them, and their distinctive characters 

 so legibly impressed as to defy misinterpretation. 



IV. — On Mr. Helland's Theory of the Formation of Cirques. 



By the Rev. T. G. Bonney, M.A., F.G.S. ; 



Fellow, and late Tutor, of St. John's College, Cambridge. 



IN the Quarterly Journal of the Geological Society (vol. xxxiii. 

 p. 142) is an important paper by Mr. Holland, on Fjords, Lakes, 

 and Cirques in Norway and Greenland. In this he notices a theory 

 of mine on the formation of cirques which was published in the same 

 journal (vol. xxvii. p. 312). As I mentioned in a note attached to his 

 paper, he somewhat misunderstands me, supposing apparently that 

 I describe only cirques of a small size, — the fact being, that, so far 

 as I know, the Alpine cirques are quite commensurate with those of 

 Norwa3\ This, however, is of slight importance. My present 

 purpose is to give reasons why, after further observations in the 

 Alps and Pyrenees, and even in the British Isles, I still prefer the 

 explanation then advanced, that the cirques are mainly produced 

 by the combined erosive action of streamlets, to the one given by 

 Mr. Holland, that a cirque is a result of glacial action. 



I must first remark that in the Alps the persistency in direction, 

 which he observes in the Norway and Greenland cirques, is not 



DECADE II. VOL. IV. — NO. VI. 18 



