56 L. RICHARDSON AND J. W. TUTCHER : PTEROMYA CROWCOMBEIA 
VOLSELLA WICKESI Sp. nov. 
Plate IX., fig. 4. 
Type description. — Shell cylindrical, umbonal portion obtuse,, 
inflated, margin straight, keel not well defined. 
Kemarks. — This form — which we name after Mr. W. H. Wickes, 
of Bristol, who was the first to publish an account of the Rhsetic and 
Lower-Lias sections of Redland,* whence the type specimen of this 
species came — is readily distinguished from other Volsellce from the 
Pleuromya-Beds by its obtuse inflated umbonal region, straight anterior 
margin and the indefiniteness of its keel. It is not common and 
appears to be confined to the Pleuroniya-Beds. 
EXPLANATION OF PLATES. 
Plate VIII. 
Figs, la, b, c, and 2. — Pteromya crowcombeia Moore. (See p. 5L) 
la=Left valve, nat. size ; lb enlarged ( x 2) ; 2 right valves ( x 2.)' 
Horizon. — Pteria-contorta or Lilstock Beds. lihsetic. 
Locality. — Blue Anchor, near Watchet, Somerset. 
Collection. — L. Richardson. 
Figs. 3a, b, and c. — Pleuromya tatei nom. nov. (Nat. size.) (See p. 52.) 
3a=right valve ; 3b umbonal view of the same valve ; 3c=left 
valve. 
Horizon. — Pleuromya-Beds. Lower Lias. 
Locality. — (3a and b) West Hatch, near Taunton, Somerset ; (3c) 
Aust Cliff, near Bristol. 
Collection. — J. W. Tutcher. 
Fig. 4. — Pleuromya tatei nom. nov. var. altior nov. (Nat, size.) (See 
p. 52.) 
Horizon. — Pleuromya-Beds. Lower Lias. 
Locality. — Filton, near Bristol. 
Collection.— 3 . W. Tutcher. 
Fig. 5. — Pleuromya tatei nom. nov. var. langportensis nov. (Nat. size.) 
(See p. 53.) 
Horizon. — Langport Beds. 
Locality. — Radstock Grove, Radstock, Somerset. 
Collection.— :S . W. Tutcher. 
* Proc. Bristol Nat. Soc, Vol. IX., pt. 2 (1899), pp. 99-103. 
