132 TELLINIDZ. 
Philippi, stated to be cirrhated at their apertures; foot not 
very large, without byssal groove. Nothing is said in either 
account of the branchiz, and Philippi only observes that the 
animal has very “large oval palpi”; from which we hazard 
an opinion that it may belong to our second section, in which 
there is only one compound branchial lamina, and excessively 
large palpi on each side of the body. In these extracts we 
have a strict description of a true Tellinidan, of either the first 
or second section. The teeth also are those of a Tedlina, either 
without or with obsolete laterals. Diodonta therefore is only 
synonymous with a Tellina of one or other of the sections. 
But if, from the very considerable variation of animal structure 
in the two divisions, it should be thought advisable to con- 
stitute a distinct genus for the second section, with the single 
compound branchia on each side, and Diodonta should realize 
our conjectures as to a similar form of the organs, it would 
have priority over any other generic term, and in that case 
would receive as congeners 7’. tenuis, T. solidula, and perhaps 
T. fabula. 
These are the reasons that have induced us provisionally to 
deposit the 7. fragilis in the second section, until we have 
further information on the required points.. And we invite 
naturalists who are in the vicinity of this interesting species 
publicly to record their notes. 
LUCINOPSIS, Forbes and Hanley. 
The Venus undata of the older conchological authorities, 
which has been justly separated from Venus by more recent 
writers under various appellations, and particularly by the 
learned authors of the ‘ British Mollusca’ under the title of 
Lucinopsis undata, has given rise to much difference of opimion 
amongst malacologists in regard to its natural position. 
Though the shell of this species, anomalous in several points, 
has long been known, the aggregation of the curious charac- 
ters of its animal has never been sufficiently described, from 
the difficulty of procuring it alive of large size. The quotation 
from my manuscript in the ‘ British Mollusca’ is the result of 
