222 SUPPLEMENT TO THE 



Haswell, J. Ileiidcison, J. D. l^rowii, and myself; hence resulted the discovery of twenty- 

 seven species. Some of these were briefly described by the observers above named, 

 but more fully by myself in the ' Transactions of the Geological Society of Glasgow ' for 

 the year 1808.^ The few Llandeilo Brachiopoda of the Moffat series were discovered and 

 collected by Mr. J. Stevens, and Profs., H. A. Nicholson and C. Lapworth, and will be 

 found figured and described in ray Monograph. Two species of Brachiopoda were also 

 obtained by Messrs. Slimon and Page from the Upper Silurian rocks of Lesmahago 

 and have been illustrated by myself in the ' Transactions of the Glasgow Geological 

 Society.' 



It is, however, to the able and indefatigable exertions of Mrs. Robert Gray, of Edin- 

 burgh, during the last twenty or more years, that the most important advance to our 

 knowledge with respect to Scottish Upper- and Lower-Silurian Brachiopoda is due. Mr. 

 and Mrs. Gray have collected in the Girvan district during a portion of each successive 

 year since about 18C0, carefully noting the horizons and localities from which each of their 

 specimens had been obtained ; and with great liberality they have placed their very large 

 collections of Brachiopoda in my hands for description and illustration. Prof. C. 

 Lapworth has likewise afforded me much valuable information and help by giving me 

 the exact horizons from which Mrs. Gray's fossils have been obtained. Hence I have 

 been able to describe and determine upwards of 100 species, of which a great number 

 have proved to be quite new and special to the districts, and unknown from any other 

 British formation or locality. 



I must now mention with great praise the important and most useful ' Catalogue of 

 the Western-Scottish Fossils,' prepared by Messrs. James Armstrong, John Young, 

 and David Robertson, 187G. This valuable work, which reflects great credit on the 

 gentlemen above named, contains lists of the Scottish Brachiopoda known to them up 

 to the period of its publication : these lists, taken to a great extent from my ]\Ionograph, 

 were forwarded to me for revision. 



By order of Prof. A. Geikie, Director-General of the Geological Survey of Great 

 Britain, Mr. B. N. Peach kindly forwarded to me for examination all the Brachiopoda 

 collected by the Geological Survey of Scotland from several Scottish Counties, and I have 

 therefore had the advantage of having been able to study nearly all the specimens of this 

 class hitherto obtained in Scotland ; and their descriptions and figures will be found in 

 my ' Silurian Monograph ' and its ' Supplement.' 



The following eight Scottish Counties have furnished us with Silurian Brachiopoda, 

 viz. Midlothian, Lanarkshire, Peeblesshire, Dumfriesshire, Kirhcudbrightshire, Berwick- 

 shire, Sutherlandshire, and Ayrshire. I feci also convinced that a larger number of 

 species will, with time, be obtained from the Counties above named, and 1 hope that 

 geologists will continue their search for fossils. 



1 A. Bou6, who explored the Peutland Hills aud North Esk locality in IS 13, did not find a 

 single fossil. In 1835 Mr. R. J. Cunningham and myself examined the same places, find did not find 



