THE CARBONIFEROUS OSTEACODA OF THE CLYDE 



DRAINAGE AREA. 



BY PROF. T. RUPERT JONES, F.R.S., AND (THE LATE) 



JAMES W. KIRKBY. 



THE Ostracoda found in the Carboniferous strata of Western Scotland are 

 obtained from certain fossiliferous beds in each of its chief divisions, viz. 

 the Calciferous Sandstone series, the Lower Limestone series, the Middle Coal 

 and Ironstone series, the Upper Limestone series, and the Upper Coal and 

 Ironstone series. The division, however, which has yielded the greatest 

 number of genera and species is the Lower Limestone and its accompanying 

 shales, chiefly of marine origin. In the strata, believed to be of lacustrine 

 or freshwater origin from their fossil evidence, and from the absence of 

 characteristic marine remains, as in the case of those strata which compose 

 the Lower and Upper divisions of the Coal and Ironstone series, there are 

 found certain forms of a small group of Ostracoda highly characteristic of 

 these so-termed lacustrine conditions, and some of the species of which are 

 found to range in time from the lower to the higher beds. The Ostracoda, 

 wherever they appear, have evidently been very abundant in the waters in 

 which these strata were being deposited, as their minute shells are often seen 

 to have largely contributed to the formation of the beds. As a general rule 

 they are hardly ever found mingling with the characteristic marine forms, 

 which shows that the conditions under which the two groups lived were 

 different. 



The species of the group have been, so far as discovered, very fully 

 determined, described, and figured, thanks to the long-continued labours of 

 Prof. T. Rupert Jones, F.R.S., and Mr. James W. Kirkby, 1 who have made 

 its study one of their chief specialities, culminating in the publication of 

 their Monograph on the Carboniferous Ostracoda issued by the Palaeonto- 

 graphical Society in 1874 and 1884 Extracted from a paper by the late Dr. 

 John Young, F.G.S., read before the Geological Society of Glasgow in 1891. 2 



Other important memoirs by Prof. Jones and Mr. Kirkby with figures and 

 descriptions of the same subject have been published in the following : 



Annals and Magazine of Natural History, 1865, 1866, 1875, 1879, 1885, 

 1886, 1892, and 1895. 



Transactions of the Geological Society of Glasgow, 1869. 

 Quarterly Journal of the Geological Society, 1879. 



1 A few weeks before this article was put in type the regretted death of Mr. Kirkby 

 occurred. Consequently the list has not had the benefit of his supervision. 



2 "Notes on the group of Carboniferous Ostracoda found in the strata of "Western 

 Scotland, with a revised list of Genera and Species." By John Young, F.G.S., V.P. 

 Trans. Geol. Soc. of Glasgow, vol. ix., part 2, 1893, p. 301. 



