POLLICIPES. th 
Species aliquot quas, scutis incognitis, auctores a valvis insignibus nomindrunt, hie pro 
tempore solummodo iterum describuntur. 
Species named by authors from remarkable valves, but their scuta being unknown are 
here only provisionally re-described. 
21. Potuicipzs BRronnu. ‘Tab. IV, fig. 10. 
POLLICIPES BRONNII. F'. Roemer. Verstein. Norddeutschen Kreidegebirges, p. 103, 
Tab. xvi, fig. 8. 
P. cariné levi, subcarinatd, margine basalt arcuato et turgido ; tota valvd vel extrorsum 
arcuaté vel pene recta ; interne, costis duabus elevatis ad utrumque latus partis superioris 
liberé prominentis. 
Carina smooth, subcarinated ; basal margin arched and protuberant; whole valve 
either outwardly bowed or nearly straight. Internally, the upper, freely-projecting portion, 
has on each side a prominent ridge. 
Upper Greensand, Warminster, England. Mus.J.Tennant. Hils-conglomerat bei Essen. Mus. Univers., 
Copenhagen. 
My materials consist of some specimens lent me by the kindness of Professor Steen- 
strup; they consist, as well as those described by Roemer, only of the carina; their sur- 
faces are considerably worn. ‘The Hils-conglomerat of Essen is considered by Roemer as 
the equivalent of one of the lower beds of the Lower Greensand; but recently MM. 
Saemaan and Geinitz have shown that it really corresponds with the Upper Greensand. 
Professor Tennant has lent me a single broken cara from Warminster, which cannot, in 
our present state of knowledge, be specifically separated from the typical continental 
specimens, though, as we shall see, slightly differing from them. 
I will first describe the foreign specimens. 
Carina (Tab. IV, fig. 10) strong, massive, triangular, about twice as high as broad ; but 
what bowed inwards; basal margin not in the least protuberant; not carinated, but steeply convex, so that 
a section of the base (4) has steeper sides than a semi-circle. 
Diagnostic characters. 1n comparing the scuta of P. rigidus, fallax, and elegans, the latter can be at 
once distinguished from P. fallax by the ridge running from the apex having perpendicular or wall-sides, 
and by the straightness of the basal margin; from P. rigidus, by the ridge being much broader; P. fallax 
differs from both, in the absence of longitudinal striz. In the terga, P. elegans differs from both P. rigidus 
and fallaz, in the ridge running from the apex to the basal angle being straight, and in its greater breadth, 
and likewise in the shortness of the upper carinal margin. The terga of P. fallax differ from the homo- 
logues of the other two species, in the ridge connecting the upper and lower points, not having perpendicular 
sides. 
