ill!Ill

BERKELEYA.
GENUS 18. BERKELEYA (GREV. 1827), H. VAN HEURCK,
Emend.
Valves with central nodule sub-divided, divisions more or less
separated. Raphe absent between the divisions of the nodule.
Frustules naviculoid, enclosed in mucous tubes as in the Schizonema.
f
ANALYSIS OF SPECIES.
r ('About 32 strife in i c.d.m. B. fragilis.
Valves sublinear, narrow ; strire quite parallel \
( About 26strire in 1 c.d. m. B. micans.
. Valves elliptical-lanceolate, median strire parallel, terminal radiate . . B. Dillwynii.
OT
s
I
Fig 45
294 ;
245
B. fragilis Grev. (Scot. Crypt. Flor. pi.
H.V.H.
Atl., pi. 16, f. 12).
Valves linear, narrow, and very elongated ; sub-
divisions of central nodule rather approximate ; striae
quite parallel, delicate, 32 to 40 in 1 c.d.m. Length,
about 8 c.d.m. Breadth, about 0-4 c.d.m.
Marine. Not yet discovered in Belgium. England (Mrs. Griffiths).
Scotland (Grev., Arnott), Eulen, Type No. 80. Ireland (O'Meara).
France, Brest (Coronan) ; Cherbourg
(Bre'bisson).
Prof. Cleve makes B. fragilis only a variety of the
following :
B. micans (Lyng.) H.V.H. (H.V.H.
Atl., pi. 16, f. n* ;
Type No. 156), plate 5, fig. 254.
Valves linear, narrow and very elongated ; sub-
divisions of central nodule rather distant ; striae
parallel, delicate, 26 in 1 c.d.m. Length, 8 to 9 c.d.m.
Breadth, 0-4 c.d.m.
Marine. Not yet discovered in Belgium, but found in France,
Holland and Denmark.
B. Dillwynii (Agardh) H.V.H. (H.V.H.
Berkeleya fragilis. Atl., pi. 1 6, f. 1 5* J Type No. 157), plate 5, fig. 255,
Valves elliptical lanceolate, narrow, with divisions of central nodule more
or less distant. Median striae parallel, terminal radiate, delicate, 30 in 1
c.d.m. Length, 1*5 to 3-5 c.d.m. Breadth, C4
-
to o 6 of c.d.m.
Marine. Ostend (West. 895 sub. Schizonema rutilans). Ostend leg. (Grunow). England
(Kitton), Scotland (Eulen, Type No. 81, 82).