198 THE ESSEX NATURALIST.
of rocks in the littoral and laminarian zones, and having des-
cribed it as "small and distorted," figures a specimen, the
only one in his collection (now at Washington), in Brit. Conch.
v., pl. xxi., 50mm. long, which Dr. Dall tells me represents the
shell very exactly, as against Lamarck's 8-11 mm. Reeve
(Ostrea, pl. v.) figures another of Jeffrey's specimens, varying
in some respects from Jeffreys' figure, and much larger.
According to Jeffreys some specimens resemble the Gryphaea
in shape. Was he confusing it with the Portugese shell O. angu-
lata, having mixed his memoranda ?
Brocchi (Conch. foss. Subap.) describes a small shell which he
names pusilla. 14 mm. in length, of which I have three examples
from the Coralline Crag. They seem fully grown, and may
be the same or allied to Lamarck's shell and like it are hollow
under the hinge line. Continental writers are not much more
definite, and neither Monterosato, Sacco, Seguenza, Cerulli-
Irelli or Hidalgo refer to it. Carus merely says O. edulis var. a-
crassa, lamellis appressis." Prof. Issel "O. hippopus Lam.,
var. tarentina." Philippi makes it a variety of O. bellovacina,
an Eocene fossil, and MM. Bucquoy and collaborators O. lamellosa
Brocchi. It does not agree however with Sacco's later figure of
Brocchi's type.
VAR. TINCTA Jeffreys.
"Shell flattened and attached at every stage ; inside of a
rich purplish brown, or olive green ; hinge margins strongly
crenulated." West of Scotland and Burra Isles, Shetland
(B.C. ii., p. 39, but not figured). Reeve adds "regularly formed
and flat."
It does not appear that Jeffreys had noticed this form prior
to the issue of the British Conchology, and all we have hitherto
known of it has been derived from the above meagre description
and the figure of the inside of the lower valve showing the colouring
in Reeve (Conch. Icon., Ostrea, pl. v., fig. 8, c.)
It is somewhat rare, being very local. I possess a fine speci-
men kindly sent me from Jeffreys' collection by Dr. Dall, and I
have also received from Mr. James Young, of Lochalsh, N.B., a
small series from Scalpa Sound, near Skye, and these enable me
to complete the imperfect diagnosis quoted above, as follows :—
Ovate (in young examples) to subtrigonal, apex nearly central,