238 



THE GEOLOGIST 



prosecuting a study wMcli would from its complication liave lost all 

 those charms which Nature lays open to the studious mind. 



A correct section of the British Carboniferous System, with a list 

 of the species peculiar to each zone or stage, as well as of those which 

 possess a greater vertical range, is, as we have already stated, a great 

 desideratum, and is a subject well worthy of the attention of the 

 geologist and palaeontologist. Such an investigation is being carried 

 out by Doctors White and Oppal, Prof. Suess, Mr. Eugene Deslong- 

 champs, and others with reference to the Jurassic strata ; and the 

 others systems have been likewise to a greater or lesser extent 

 similarly investigated ; but the Carboniferous one (which is so far 

 spread and so important) appears to have been in reality less com- 

 pletely and carefully studied with respect to the distribution of its 

 species than almost any other ; although we possess many valuable 

 works by several of our most eminent geologists and paleeontologists 

 in which the system and fossils have been minutely described. Two 

 great helps which recent species afford are almost entirely precluded 

 from the palaeontologist, that is to say, the power of being able to 

 anatomically examine the animal, and the absence of that coloration 

 which is often of so much assistance in the discrimination of recent 

 shells ; and when we reflect how vivid, beautiful, and varied must 

 have been the tints which once adorned the now black and dingy- 

 fossil, we ai'e delighted when, by some fortunate accident, some re- 

 mains of that colour is faintly preserved upon a shell which has, for 

 almost countless ages been concealed from the sight of man. The 

 interiors and well preserved internal casts should likewise be care- 

 fully collected, for upon them are impressed many signs which can be 

 interpreted by the experienced palaeontologist, and lead him to re- 

 construct and describe many characters in an animal of which no 

 living representatives may at present exist. 



In the first pages of this paper, we endeavoured to give some brief 

 and general idea of the principal divisions into which the Carbon- 

 iferous system had been divided, as well as some details regarding 

 that of Scotland in particular. Since then, Mr. Geikie, of the 

 Geological Survey of Scotland, has kindly transmitted to me the 

 annexed tabular view of the Carboniferous series of the Lothians, and 

 which appears to be nearly the same as in the western districts. In 

 the Lothians, the Brachiopoda range only in that portion of the 

 system, or section, which corresponds to the Carboniferous limestone 

 of England, some species ranging from the top to the bottom of this 

 division, but the greater numlDer appear confined to the lower lime- 

 si one series. Lmgula mytiloides is stated by Mr. Geikie to be in the 

 Ijothimis characteristic of a zone about the middle of the Edge Coal 

 series ; but more information may be expected as soon as the Survey 

 shall have published the results of their careful and assiduous labom^s. 



Mr. George Tate, whose knowledge of the Carboniferous system is 

 well kno^vn, has, at my request, favoured me also vdili a note upon 

 his "Tweedian group," which we will here transcribe, as it will explain 

 the views of tliat excellent observer, as developed relative to some of 

 the oldest beds of the system in Berwickshii-e and Northumberland. 



