NEW FORMS OF MARINE DIATOMACEX, 505 
narrow, and, but for the absence of apiculi, a miniature of that of Apr. lepidop- 
tera. (See farther on, fig. 59 b.) Both views, and also the plates, are marked with 
very fine transverse and parallel strive, which, however, on the F.V. do not ex- 
tend to the rectangular space between the valves. - Strize about 60 in 0-001’. 
This pretty little species has occurred only in one of the Loch Fine dredgings, 
where it is rather scarce. It is remarkable for the occurrence of the lateral 
plates, which we shall find in several other species, and which perhaps ought to 
constitute a new genus. But the resemblance to Amphiprora is so great in other 
points, that I do not think it advisable to separate these species from that genus. 
57. Amphiprora plicata, n. sp. Pl. XIL, fig. 57. F.V. deeply constricted, with 
rounded extremities, which are very broad. Inner margin of valves straight. 
On each valve lies a plate extending from the inner margin of the valve to the 
nodule; its outer or convex margin being a little incurved in the middle, and 
bent forward at the ends, to join the inner angles of the valve. The rectangular 
space joining the two valves is marked with faint vertical lines or folds; and the 
valves and lateral plates, as well as the rectangular space, are all marked by fine 
transverse strize, about 50 in 0-001". Length 0-0037’; breadth from nodule to 
nodule 0:00075", at broadest part 0:0016’. Outer margin double. S,V. not yet 
certainly known. 
This species occurs with the preceding, and is equally scarce. It approaches 
nearest to Apr. alata, but differs from it in the folds of the middle space, and in 
the presence of the lateral plates. 
58. Amphiprora elegans, Sm. PI. XII, figs. 58 and58 5. Form of S.V. linear- 
lanceolate, ends obtuse. Valve traversed by two longitudinal lines, and marked 
by fine but distinct transverse striz. Length from 0:0085’ to 0:012’; breadth of 
S.V. about 0:0011". F.V. rectangular, with two longitudinal lines. Strize 44 in 
0:001", parallel. 
I have figured the 8.V. of this fine form, first noticed by Mr Birax.ey, be- 
cause, although described in vol. ii. of the Synopsis, no figure of it has yet appeared. 
It occurs both in the Glenshira Sand, and in more than one of the dredgings ; but 
more frequently in one of those from Loch Fine than in any of the others. The 
valves are, in these deposits, generally detached, so that I have not met with the 
entire F.V. Iam indebted to Mr Rorer for an entire specimen, fig. 58 b. 
59. Amphiprora lepidoptera, n. sp. Pl. XIL., figs. 59, 596, and 59c. Form of 
FY. linear, constricted in the middle, expanded at the apices, which are flatly 
‘rounded. Length from 0:0055" to 0-008"; breadth of F.V. in the middle 0-0009’, 
near the ends 0°0015’. SV. lanceolate, with acute ends, terminating in small api- 
culi. Central nodule strongly marked; median lines somewhat curved, meeting 
in the nodule. Striation fine, parallel, about 48 in 0-001’; on the F.V. the strize 
are absent from the middle space. The form of the F.V. with its long slender 
alee, is very elegant. 
VOL. XXI. PART IV. 6U 
