RECENT AND TERTIARY SPECIES OF LEDA AND NUCULA. 171 
like a Solenella, and it partakes indeed of some of the 
characters of that genus, as well as of Nucula and Leda, and 
were it rostrated it would be referred to the latter. It is 
quite of a different type to the Nuculas which follow, and to 
those like N. nucleus. 
3. Nucula vieta, Guppy (PI. vii., f. 11). 
Proc. Scientific Assoc. Trinidad, 1867, p. 174. 
Geological Magazine, 1874, pi. xviii. , f. 8. 
A Nucula of obliquely subtriangular form, like N. proximo, 
and N. mixta, with regular round concentric ribs. Small 
specimens only have occurred in the Pliocene of Trinidad, 
but it would not be surprising if it proved to be also a recent 
shell attaining greater dimensions than those we have seen, 
the largest of which are 3| mill, in height and 3 mill, in 
breadth. 
4. Nucula baccata, Guppy (PI. vii., f. 12). 
Proc. Scientific Assocr. Tinidad, 1867, p. 174. 
Geological Magazine, 1874, PI. xviii., f. 7. 
A Nucula of the group of N. obliqua and N. similis , some- 
what similar in style to N. vieta, but distinguished by its less 
triangular form, greater size, and almost smooth surface. 
The margins of both species are crenulate. N. baccata has 
only hitherto been found in the Pliocene of Trinidad. Our 
specimens measure 7 mill, in breadth, and 5-| mill, in height. 
As nearly all the shells of living species found in the Pliocene 
(Matura) beds of Trinidad are smaller than their living repre- 
sentatives, it may be anticipated that if any of those now 
known only as fossils are discovered to be living, the recent 
examples will be of larger size. 
