Fossils from Mulde, Gotland. 151 
valve excavated and granulate. The central area is occupied 
by three transverse narrow lobes or ridges, which are all 
slightly salient at the dorsal border; the posterior and central 
lobes are slightly clavate ; the anterior is a thin ridge and 
joining the raised border of the valve at the antero-dorsal 
angle. Length of carapace ‘8 millim.; height *4 millim. 
This is a very neat form, and apparently has not been 
previously noticed in any of the washings made from the 
Silurian either of this country or of Gotland, The nearly 
symmetrical W-like group of the three thin central lobes, 
scarcely reaching the ventral region and joining on with the 
anterior marginal rim, is not matched in any published 
figures. A somewhat near approach to these features, how- 
ever, is seen in B. admixta, Jones & Holl *, from Woollhope, 
but that form is more stoutly built and its four transverse 
lobes are thicker and shorter in proportion; their general 
arrangement is also different. 
Silurian; Mulde, Gotland. Frequent. 
Beyrichia Jonesii’, Boll. 
Beyrichia Jonesit, EK. Boll, 1856, Zeitschr. deutsch. geol. Gesellsch. 
vol. viii. p. 322, figs. 1,2; 1862, Archiv Ver. Fr. Nat. Mecklenburg, 
16 Jahr. p. 134, fig.8; Jones & Holl, 1886, Ann, & Mag. Nat. Hist, 
ser. 5, vol. xvii. p. 359. 
This has already been recorded from the Wenlock Lime- 
stone of Hastnor Park. A few typical specimens with 
faintly granulate surfaces occur in this collection, 
Silurian; Mulde, Gotland. 
Beyrichia Kledeni, M‘Ooy, var. tuberculata, Salter. 
Beyrichia Kledeni, var. tuberculata, Salter, 1881, Geol. Mag. dee. ii. 
vol. vill. pp. 345, 846; Jones & Holl, 1886, Ann. & Mag. Nat. Hist. 
ser, 5, vol. xvil. pp, 354, 355, pl. xii. figs. 8a, b, 9a, b. 
Most of our specimens can be compared with the subvariety 
clausa, by which Jones and Holl have designated certain 
small elongated examples from the Wenlock Shales in Vine’s 
collection, and these are possibly young individuals. There 
is, however, one example of the typical variety in our series. 
Silurian; Mulde, Gotland. Rare, 
Beyrichia tuberculata (Klceden), var. lineato-tuberculata, nov. 
(Pl. III. fig. 11.) 
This is one of the many modifications of B. tuberculata 
* Ann. & Mag. Nat. Hist. 1886, ser. 5, vol. xvii. p. 359, pl. xii. fig. 5. 
