Fossils from MuldCy Gotland. 151 



valve excavated and gramilatu. The central area i.s occupied 

 by three transverse narrow lobes or rid<;cs, which arc all 

 slightly salient at the dorsal border ; the posterior and central 

 lobes arc slightly clavate j the anterior is a thin ridge and 

 joining the raised border of the valve at the antero-dorsal 

 angK'. Length of carapace "8 niillim. ; height "4 inillini. 



'Jhis is a very neat form, and apparently has not been 

 previously noticed in any of the washings made from the 

 Silurian cither of this country or of Gotland. The nearly 

 symmetrical W-like group of the three thin central lobes, 

 scarcely reaching the ventral region and joinijig on with the 

 anterior marginal rim, is not matched in any published 

 figures. A somewli;it near a])proacli to these features, how- 

 ever, is seen in B. admixUi, Jones & lloU *, from Woolhope, 

 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. 



Bexjrichia Jonesii, Boll. 



Beyrichia Jvnesii, E. Boll, 18o6, Zeitsclir. deiitsch. geol. Gesellscb. 

 vol. viii. p. 322, ligs. 1, 2; 18G2, Archiv Vor. Fr. Nat. Mecklenburg, 

 16 Jalir. p. 134, tig. 8 ; Junes & IIoU, 1880, Ann. vt Mag. Nat. Hist, 

 ser. 5, vol. xvii. p. 35i>. 



This has already been recorded from the Wenlock Lime- 

 stone of Eastnor Park. A few typical specimens with 

 fiiintly granulate surfaces occur in this collection. 



Silurian ; Mulde, Gotland. 



Bci/richia Kla:deiu\ jNI'Coy, var. tuberculata, Salter. 



Beyrichia Kladeni, var. tuhercidata, Salter, 1881, Geo). Mag. dec. ii. 

 vol. viii. pp. 34o, 316; Jones & lloll, 1886, Ann. & Mag. Nat. Hist, 

 eer. o, vol. xvii. pp. 354, 355, pi. xii. tigs. 8 a, i, \i «, b. 



Most of our specimens can be compared with the subvariety 

 claiisUf by which Jones and IIoll have designated certain 

 small clongatetl examples from the Wenlock Slialcs in Vine's 

 collection, and these are possibly young individuals. There 

 is, however, one example of the typical variety in our series. 



Silurian; ^lulde, Gotland. Rare. 



Beyrichia tuberculata (Kloedcn), var. lineato-tuherculata, nov. 

 (Fl. IlL i\'^. 11.) 



This is one of the many modifications of B. tuberculata 

 * Ann. & MhP- Nat. Hi.>*t. 1886, ser. o, vol. xvii. p. .V)9, pi. xii. lig. 6. 



