Messrs. Jones and Kirkby on Carboniferous Entomostraca. 35 
distinctions for nominal varieties. Thus L. Scotoburdigalensis 
may be allowed to stand as a sufficiently distinct variety of L. 
Okeni, though possibly it really differs only in having been 
dwarfed by unfavourable circumstances of growth. 
In the Lower Carboniferous shales and limestone of Burdie- 
house* we see Leperditia Scotoburdigalensis in company with 
Spirorbis (Microconchus) carbonarius (not very abundant there), 
abundant Fish-remains, Lepidodendron, Lepidostrobus, Spheno- 
pteris, &c. 
This smallest of the many varieties of Leperditia Okeni, oc- 
curring in the Lower Carboniferous limestones and shales of 
Great Britain and Ireland, has been found at Burdiehouse (by 
Hibbert, Horner, Binney, Sorby, Crosskey, the Geological Sur- 
veyors, and others) ; Granton (Harkness) ; Pittenweem, in Fife- 
shire (Hunter) ; Bathgate (Young); Arundale, near Bathgate 
(Young); Hurlet, S.W. of Glasgow (Crosskey); Carluke (Ran- 
kine); Lammerton and Cockburnspath, Berwickshire (G. Tate); 
and at many places in Ireland by Sir R. Griffith and the Geo- 
logical Surveyors. (See further on.) 
One of us long ago saw that this little Entomostracan could 
not be a Cypris, nor a Cythere, and put it with Cytheropsis (a 
provisional genus). Hence it appears under that name in the 
‘ Monograph of the Fossil Estheriz’ (Paleontographical Society, 
1862) and in some other works. It was definitely referred to 
Leperditia by us m 1863 (Brit. Assoc. Report, 1863, Sections, 
p- 80; and ‘ Geologist,’ vol. vi. p. 460). 
1836. Bean.—In 1836 Mr.W. Bean, of Scarborough, described 
in the ‘ Magazine of Natural History,’ vol. ix. p. 377, a little 
Entomostracan from the Coal-measures of Newcastle-upon-Tyne, 
as Cypris arcuata; and illustrated it by a woodcut (fig. 55). 
This is really a Beyrichia, and has been so referred to, on the 
authority of one of us, for several years past. 
Beyrichia arcuata is one of the most widely distributed Ento- 
mostraca in the Coal-measures of England and in the “ Upper 
Coal-measures” of Scotland. It has also been found in the 
shales of the so-called ‘ Millstone-grit ” of Lancashire and in 
the Lower Carboniferous shales of Scotland, but not in the 
Mountain-limestone, or equivalent portions of the Carboniferous 
Series, in England. We have it from the Ryhope Colliery, near 
Sunderland, in shale, about 8 or 10 feet below the base of the 
Permian strata ; from Claxheugh, near Sunderland, in ironstone ; 
from Hylton, near Sunderland, in ironstone; from Prestwick, 
Northumberland,in carbonaceous shale (Atthey); fromLoughton, 
* For a full account of the Carboniferous Strata of Burdiehouse, see 
the ‘ Memoirs of the Geol. Survey,’ &c.: ‘“ Geology of the Neighbourhood 
of Edinburgh,” by Howell and Geikie, 1861, p. 36, &c. f 
3 
