122 ON PERMIAN ENTOMOSTRACA FROM 



an almost indefinite period under water, even where there is a 

 constant and free access to the salt tides of the ocean. 



XIV. — On Permian Entomostixica from the Shell-Limestone of 

 Durham. By J. W. Kirkby. With Notes on the Species ; by 

 T. KupERT Jones, F.G.S. 



The descriptions by Mr. Rupert Jones in Professor King's " Mono- 

 graph of the Permian Fossils of England," form the first notice 

 of Permian Entomostraca. In this work Mr. Jones describes 

 several species, principally from the upper beds of the Permian 

 rocks of Durham.* In 1856, Professor King noticed the oc- 

 currence of a single species {Cythere inornata?) from the Per- 

 mian limestone near Tullyconnel, in Tyrone. | And in No- 

 vember last year (1858), I made some remarks on some species 

 from the shell-limestone of Tunstall Hill, in the " Annals of 

 Natural History. "J No other observations have been made on 

 Permian Entomostraca in Britain. 



In 1854, Dr. Reuss described ten species from the Permian ' 

 rocks of Germany, They were obtained from the Unter Zech- 

 stein of Bleichenbach and Selters, in the Wetterau.§ Some of 

 the species he considered to be new, others to be identical with 

 forms found in the upper Permian beds of Durham. 



In the same year six new species were described by Count 

 Alex. Von Keyserling, from the Permian rocks of Russia. || 



In 1855, Dr. Richter noticed the occurrence of eight species 

 in the Unter Zechstein of Saalfeld. Among them was one form 

 considered to be new ; the rest were referred to species that had 

 been previously described by Jones and Reuss.^ 



The following remarks refer more particularly to the Entomos- 



* " Monograph of Term. Foss. of England," pp. 58-66. 



t. " Journal of the Geological Society of Dublin," vol. vii., p. 78. 



X " Annals and Magazine of Natural History," 3rd series, vol. ii., pp. 317 & 434. 



§ " Jahresbericht der Wetterauer Gesellschaft, 1854," pp. 65-70. 



II "Reise durch die Tundren der Samojeden, Dorpat, 1854," pp. 111-113, pi. 4. Permian 

 Entomostraca were observed in Russia previous to this date ; but the notices of them merely 

 mention the fact of their occurrence, without specific details. See Table of Formations of 

 the Government of Simbirsk of Jaaykow, 1844, Petersb. Miner. Gesellsch. 



^ " Zeitschr. der Deutsch. Geol. Gesells.," vol. vii., pp. 5'26-533. 



