54 L. RICHARDSON AND J. W. TUTf'HER : PTEROMYA CROWCOMBEIA 
VOLSELLA HILLANOIDES (CHAPUIS AND DEWALQUE). 
Plate IX., figs. 8a and h. 
1855. Chapuis and Dewalque, Description des Fossiles des Terrains 
Secondaires de la Province de Luxembourg, p. 185, plate xxv., fig. 3. 
Remarks.- — This is the characteristic Volsella of the lower Angu- 
lata-Beds (Hemera marmorece) of England. Chapuis and Dewalque's 
type came from about the same horizon at Muno. 
We agree with Tate* in regarding V olsella psilonoti (Quenstedt)| 
as a synonym of Volsella hiUanoides (Chap, and Dew.) 
VOLSELLA L^VIS (j. SOWERBY). 
Plate IX., fig. 5. 
1812. Mineral Couchology, Vol. I., p. 30, plate 8. 
Remarks. — Sowerby's type was gathered in the ruins of Caer- 
philly Castle," near Cardiff, probably from Lower-Lias limestone 
belonging to the Pleuromya-Beds. 
Mature specimens of this species are readily distinguished from 
Volsella minima (J. Sowerby) (see plate IX., figs. 2 and 3, of this 
paper), by their more mytiliform aspect. 
All our specimens were obtained from the PUjiromya-Beds, and 
are particularly abundant in the neighbouiliood of Bristol. 
VOLSELLA LANGPORTENSIS Sp. UOV. 
Plate IX., figs 7 and lla and 6. 
Type-description. — Shell rather iiiore than twice as long as 
high ; inferior margin slightly arcuate ; hinge-line straight and 
about half the length of the shell ; margin from the end of the 
hinge-line to the posterior end slightly convex, then sharply 
curved to the inferior border ; keel well marked, dividing the 
valves into two almost equal portions ; anterior lobes prominent. 
Var. angustiformis, var. nov. (fig. 12). — Differs in being a 
narrower shell with a shorter hinge-line, more anteriorly-directed 
umbo, smaller lobe, and less distinct keel. 
Var erecta nov. (figs. 9 and 10). — More cylindrical in form, 
straighter, with a very short hinge-line. 
Remarks. — In the Langport Beds or White Lias proper are a 
number of fair-sized Volsellce which have been recorded frequently 
* The Yorkshire Lias (1871), j). 377 
t Der Jura (1858), p. 48, tab. 4, fio-. 13. 
