152 Mr. F. Chapman on some 
(Kloeden). Six of such varieties are figured on pl. xxi. 
Ann. & Mag. Nat. Hist. ser. 6, vol. i. (1888) p. 402, 
figs. 12-17, from the Silurian of Slite, Gotland. In the 
present instance the lobes are more distinctly marked with 
three obliquely transverse furrows; the ventral edge more 
neatly tubercled, and the two bold curved ventral fringes far 
more symmetrically arranged. Length 2°5 millim.; height 
1°4 millim. 
Silurian; Mulde, Gotland. Frequent. 
Beyrichia Bolliana umbonata, Reuter. 
Beyrichia Bolliana umbonata, Reuter, 1885, Zeitschr. deutsch. geol. 
Gesellsch. vol. xxxvil. p. 646, pl. xxvi. fig. 21; Jones, 1888, Ann. & 
Mag. Nat. Hist. ser, 6, vol. i. p. 401, pl. xxi. figs. 10, 11. 
This species has been recorded from Frdjel. ‘Two specimens 
were found at Mulde and are variable in size; their lengths 
measure 1°3 millim. and 2°3 millim, respectively. 
Silurian; Mulde, Gotland. 
Beyrichia clavata, Kolmodin. 
Beyrichia clavata, Kolmodin, 1869, Bidrag till Kannedomen om Sverges 
Siluriska Ostracoden, p. 18, fig. 10; Jones, 1887, Silur. Ostrac. Goth- 
land, p. 2; Jones, 1888, Ann. & Mag. Nat. Hist. ser, 6, vol. i. p. 399, 
pl. xxi. figs. 6-9. 
The washings from Mulde have yielded a very large 
number of this species, a fair proportion of them having the 
hypertrophied lobe common to this type of Beyrichia. 
Prof. Jones records B. clavata from Eksta and Fréjel in 
Gotland. 
Silurian; Mulde, Gotland. Very abundant. 
Family Cytherida. 
CyTHERE, Miller [1785]. 
? Cythere Vinei, Jones. 
? Cythere Vinet, Jones, 1887, Ann. & Mag. Nat. Hist. ser. 5, vol. xix. 
p. 191, pl. vil. figs. la, b, & 5a, b. 
A specimen similar in every respect to those found in the 
Wenlock Shales of Shropshire was met with in the Gotland 
series. ‘he generic relationship of this and the following is 
very doubtful. 
Silurian ; Mulde, Gotland. 
