Messrs. Jones and Kirkby on Carboniferous Entomostraca. 39 



and a much earlier instance of the occurrence of the genus is in 

 the Silurian Limestone of Keisley in Westmoreland, where it 

 was discovered in 1864 by Professor R. Harkness, F.R.S. 



A collection of Belgian Bivalve Entomostraca presented to one 

 of us a few years ago by M. J. Bosquet, of Maestricht, — a col- 

 lection of fossil CyprinidcE from Little Island, Cork, sent us by 

 Mr. Joseph Wright, F.G.S., — and a collection submitted to us 

 by Mr. J. H, Burrow, M.A., of Settle, Yorkshire, enable us to 

 unravel some of the obscurities of this group, which had its 

 representatives even in Silurian times*, and is still largely 

 represented in the present seas. We intend, however, on the 

 present occasion merely to mention what we believe to be 

 the real relationships of M. de Koninck^s species, as already 

 indicated in the * Neues Jahrbuch ' for 1864, p. 54, and in the 

 ' Canadian Naturalist and Geologist,' new series, vol. i. p. 237, 

 where we have stated that M'Coy's Daphnia primava is a Cy- 

 pridina, De Koninck's Cijpridina Edwardsiana and Cypridella 

 cruciata are Cypridell(B, his Cypridina annulata and Cyprella 

 chrysalidea are Cyprellee, and his Cypridina concentrica is an 

 Entomis. 



1843. PortlocL— In 1843 the late General (then Captain) 

 Portlock, in his Report on the Geology of Londonderry, 

 p. 316, treated of two Entomostraca from the Carboniferous 

 Shales of Derry, Tyrone, and Fermanagh, Ireland, namely Cy- 

 pris Scotoburdigatensis (Hibbert) and Cypris subrectus (Portlock) ; 

 and illustrated the former by fig. 13 c, and the latter by fig. 13 b, 

 of his plate 24. C. subrecia (the original specimen of which we 

 have seen, by the kindness of the officers of the Geological 

 Survey Museum, Jermyn Street) is very similar to the first- 

 named in shape, but is somewhat larger. Both are varieties of 

 Leperditia Okeni; and, together with numerous very similar com- 

 rades, they infested the salt and brackish waters of the early 

 Carboniferous period in nearly every region of the northern 

 hemisphere, acting as scavengers f on the decaying animal and 

 vegetable materials in the muddy shallows and lagoons. As 

 Leperditia subrecta represents a size above that of L, Scotobur- 

 digalensis, and does not exactly correspond to any of the Bavarian 



* In the pebbles of Silurian quartzite in the Conglomerate at Budleigh- 

 Salterton (Quart. Journ. Geol. Soc. vol. xx. p. 283; and Geol. Mag. vol. i. 

 p. 6), Mr. Salter has discovered a specimen very closely allied to Cypridina ; 

 and Mr. G. Haswell has found others in the Upper Silurian beds of the 

 Pentland Hills. 



t Since the publication of the ' Monograph of the Fossil Estheriee,' Pal. 

 Soc. 1862, in which allusion is made to the garbage-eating habits of the 

 small Entomostraca, we see that Prof. Phillips, as far back as 1841, pointed 

 out the common association of Fish-remains with Cyprids (Brit. Assoc. 

 Rep. 1841, Sections, p. 65). 



