Edwards— Descriptions of Cypreaand Marginella, 537 
nate as to obtain another remarkably fine species from the 
cutting lately made near Highgate for the Highgate and Edge- 
ware Railway. I now forward descriptions of these new 
Cypree for publication in ‘THE GEOLOGICAL MAGAZINE; 
and I avail myself of the same opportunity to correct an érror 
committed by me in the same part of my monograph, in re- 
ferring to Marginella pusilla, a species described by me from 
High Cliff, a small Marginella from Headon Hill, which I now 
propose to separate under the specific name estuarina. 
1. Cypra@a cavaTA (F. E. Edwards); Plate XIV. fig. 1 a—d. 
C. testa globosa, antice attenuata, levi: spirad prominuld, sulco 
obscuro circumdata ; apertura angusta, obliqua, elongata, levi- 
ter arcuata, ad utramque extremitatem emarginata ; labro com- 
presso, incrassato, regulariter dentato, extus marginato, antice 
depresso, cavato ; labio plicato-dentato, antice in callum fast- 
giosum ad basin tendentem lateraliter exapanso, postice in callum 
producto ; plica anticd magna, proemineniz. 
Shell globose, attenuated in front, smooth: spire apparent but 
of almost concealed by the enamel, and circumscribed by an obscured 
furrow, due to the suture. The mouth is narrow, oblique in the 
middle, curved, and produced at each end into a short, moderately 
wide canal slightly notched : the outer lip, which is somewhat flat- 
tened on the front surface and thickened externally, presents on the 
inner edge a series of teeth of which the anterior four or five are 
longer than the others; towards the anterior extremity it is flattened 
and a little hollowed out. The inner lip bears a row of pliciform 
teeth, regular and transverse—except the front one, which slants 
upwards, extending across the whole width of the inner lip—and is 
prominent, rounded, and bifureate at the point where the anterior 
canal commences, the left-hand margin of which is formed by the 
prolongation of the right furcation. The front part of the inner lip, 
like that of the outer lip, is flattened and hollowed, and is enlarged 
laterally, so as to form a ridge-like callus extending to the base. 
The posterior extremity is produced into a bluntly-rounded promi- 
nence, which forms the left wall of the posterior canal. The round- 
edly hollow depressions towards the front of the lips, and from which 
the specific name is taken, form a spoon-like trough resembling that 
found in C. oviformis (Sow.) and C. Bartonensis (Edw.). 
In the young state (fig. 1 a, b) this Cyprea much resembles an 
Ovula. The surface is covered with numerous wavy shallow fur- 
rows, finely decussated by the lines of growth ; the aperture is very 
effuse in front, and the posterior canal scarcely curved. 
The C. cavata approaches so closely to C. angystoma (Desh.) that, 
at first sight, it might be taken to be a local variety of that species ; 
but on closer examination differences appear sufficiently marked to 
render a separation necessary. In the present species the shell is 
more globose and less attenuated in front than in the French shell ; 
the aperture is less curved, the anterior and posterior canals are 
