BIVALVIA. 75 
21. Moproxta Barronensis, S. Wood. Tab, XIX, fig. 18. 
A small specimen of a Modiola, of which the figure above referred to is a repre- 
sentation, has very recently come into Mr. Edwards’s possession. It is not in a state of 
preservation sufficient for full and fair description, and I have proposed the above name 
provisionally. It appears to be covered entirely with large rays or costulz; it is more 
elongated than the fragment figured at fig. 5, Tab. X, and it has not the diversified rays 
which ornament that shell. 
22. Mopiona (°) crassistriaTa, Adwards, MS. Tab. XIX, fig. 16. 
Spec. Char. M. testé parva, ovato-trigonuld, tenut, siphoni-regione depressiusculd, 
radiatim costellatd aut crassistriatd ; costellis vel striis rotundatis, dichotomis ; umbonibus 
minimis, subterminalibus ; margine cardinali subrecto. 
Shell small, ovately triangular, thin; siphonal region somewhat depressed, covered 
with thick radiations or riblets, rounded and bifurcating ; beaks small, nearly terminal ; 
dorsal area straight. 
Length, an inch. 
Locality. Bracklesham (dwards). 
The specimen above described has recently been added to the cabinet of Mr. 
Edwards, and I have considered it, as Mr. Edwards has done, a distinct species. It 
differs from both of the previously described coarsely striated species, flabellula and 
nodulifera, being much shorter than the former, with the striae or riblets somewhat finer ; 
and from the latter, with which it agrees in form, it differs in not having the nodules of 
that species. Our present specimen is a pretty shell, and the rays with which it is 
ornamented are rounded, the spaces between them rather narrow, or at least they are less 
so than the rays themselves. The specimen adheres too closely to the matrix to permit of 
a removal, and the interior is entirely hidden. It bears some resemblance to M. pectinata, 
Lam. (Desh., ‘ Coq. foss. des Env. de Par.,’ t. 1, p. 259, pl. 39, figs. 6—8), but our shell 
is shorter, more angulated, with a comparatively longer dorsal area, and the striz are 
coarser. 
The umbo in this is nearly terminal, with a very trifling projection of the pedal 
region ; there is an uncertainty as to its correct admission into Modtola. 
11 
