Palceozoic Bivaloed Entomostraca. 353 



intermedia in 1869 from specimens found by Mr. Banks near 

 Kington in company with the typical B. Kloedeni and its var. 

 torosa (all in the state of casts). 



No. 12 in Mr. Smith's collection, from the railway-cutting 

 near Much-Wenlock, is a good example of this variety, and 

 has the exaggerated antero-ventral lobe. 



Smith Coll. .no. 12 (with "big lobe"). Kailway-cutting 

 near Much-Wenlock. 

 55i. Woolhope. (Fig. 4.) 

 Vine Coll. no. XLiVi. Bed no. 46. (Fig. 3.) 

 XLiXg. Bed no. 25. 



III. Lobes free and subdivided. 



(5) BeyricMa Kloedenij var. subtorosa, Jones. 

 (PI. XIL figs. 6 and 7.) 



Proportions :— L. 18. H. 12. 



This is a rather small semicircular form which has a distinct, 

 raised, sharp, continuous marginal rim within the curved 

 border, and the three usual lobes rather narrower than in the 

 typical B. Kloedeni. The hinder or gigot-lobe is variously 

 modified by a slight sulcation, either transverse, oblique 

 (fig. 6), or nearly vertical, sometimes double (fig. 7). These 

 marks are not often sharply defined. In some respects it 

 much resembles B. Klwdeni, var. nuda (see above, p. 351) ; 

 but the lower end of each of the outer lobes curves up more 

 definitely towards the median lobe, and the gigot is sulcated. 



In the relative narrowness of the lobes this variety • 

 approaches var. intermedia, Jones, above mentioned, and 

 more closely those individuals with the thicker lobes ; but tlie 

 very symmetrical form and the sulcate gigot-lobe connect it 

 Avith the already-published variety subtorosa. This is near 

 B. Buchiana (Ann. & Mag. Nat. Hist. 1855, vol. xvi. p. 86, 

 pi. V. figs. 1-3 ; and Proc, Geol. Assoc, Pal. Biv. Ent. 1869, 

 p. 12, fig. 13), but the valves are not oblong (except in some 

 cases with the exaggerated lobe) and the outer lobes are much 

 more curved (like the terminal margins), and not almost ver- 

 tically straight, as in var. intermedia and B. Buchiana. 



In Mr. Smith's collection is a specimen (no. 34 slide) with 

 two weak parallel oblique furrows on the gigot-lobe (tig. 7), 

 thus imitating, if not actually becoming, B. Kochii, Boll [op. 

 cit. 1862, fig. 2), which is the same apparently as B. tubcrcu- 

 lata, var. nuda, Jones {op. cit. 1855, pi. v. fig. 10, see above, 

 p. 348). This is another of those linkings between Upper- 

 Silurian Beyrichioi which would almost persuade us to group 



