J. S. GARDNER ON BRITISH CRETACEOUS NUCULIDA., 137 
while the strie are interrupted and subsequently continued on a 
new plan, this interruption haying probably led to the description 
above cited. The series from the Bristol Museum, five in all, appears 
a remarkable one; for another shell is highly distorted and has the 
beak almost overhanging the anterior margin (Pl. IV. fig. 14). JZ. 
lineata has been confounded with LZ. subrecurva in almost all Creta- 
ceous lists, and Sowerby’s name regarded as a synonym, though the 
differences between the two species or varieties are quite apparent. 
Some casts from the Grey Chalk at Dover indicate the presence of 
this species there. 
Gault species. 
Lepa Visrayeana, d’Orb., sp., Pal. Frang., Terr. Crét. vol. i. p. 172, 
pl. 301, fig. 12-14, 1843. Pl. III. figs. 17-18, 25; Pl. IV. 
figs. 26-27. 
This is a small ovate rounded shell, not nacreous, of a glossy 
brown colour with irregular lighter bands, and is the most symmetri- 
cal of all the Cretaceous Lede, the umbones being nearly central and 
the lunule inconspicuous. Itis exceedingly abundant at Folkestone, 
especially towards the upper part of the Lower Gault, and may be 
picked up in quantity on the shore, its bands of colour giving it 
a singularly recent aspect. The average length is but 10 mm., 
though exceptional specimensreach 13 mm. in length, 7mm. in width, 
and 11 mm. in height. The average dimensions of 70 Cambridge 
specimens sent me by Mr. Jesson are larger than those of the 
Folkestone specimens, yet without surpassing the largest of the 
latter*. The muscular impressions and the form of the teeth are 
very ill defined on the cast, which I find, upon an examination of the 
specimens at Cambridge, has been described by Prof. Seeley as NV. 
subelliptica and NV. rhomboidea}. Itseems to be equally common in 
the Gault of the Paris Basin, D’Orbigny’s description making it 
rather more compressed than is found to be the case in measuring 
our own very perfect specimens. 
A very thin, smooth, and flattened shell is not uncommon in the 
Upper Gault at Folkestone, where only single valves occur. It may 
be but a slightly modified form of this species, under different con- 
ditions of preservation. 
Neocomian Species. 
Lupa SEELEYI, sp. nov. PI. V. figs. 17-20. 
There is nothing to distinguish this species from ZL. Vibrayeana 
unless it be a slightly more flattened form with more rounded and 
obtusely oval extremities. Seeley’s name, originally given to L. 
Vibrayeana of the Cambridge Gault, had fallen into disuse as a 
Synonym, but is still attached to the tablet of Speeton-clay speci- 
mens in the Woodwardian Museum. It would be inconvenient to 
retain it, even restricting it to the Neocomian form; and a new 
* A length of 14 mm. is quoted by Pictet as the average of the Swiss form. 
t+ Ann. Mag. Nat. Hist. ser. 3, vol. vii. p. 120. 
