540 PKOr. T. K. JONES ON SOME DEVONIAN AND 



ly. BoLLiA, Jones and HoU, 1886. 

 Bollia, J. & H. ' Ann. & Mag. Nat. Hist.' ser. 5, vol. xvii. p. 360. 



7. BOLLIA BILOBATA, Sp. nOV. (PI. XX. fig. 12.) 



Length 1*8 mm. ; height 1 mm. 



This is a broken and worn cast from the decomposed Corniferous 

 Chert of Ontario Co., N. Y. It is probably an oblong BoUia, the 

 two lobes of which have been very prominent, but have been modified 

 by accidental rubbing, and their curved connecting ventral ridge 

 almost worn away. It is much like B. hicollina, J. & H. (' Ann. & 

 Mag. Nat Hist./ April 1886, p. 361, pi. xii. figs. 14-16), but the 

 valve is longer, being more oblong, and the lobes are much lower 

 down, away from the dorsal margin. There is also an appearance 

 of similarity to such a form as fig. 2 a, PI. XXI., but the two re- 

 stricted lobes are too far away from the dorsal margin ; and the 

 marginal lobe is at the contrary end of the valve, and herein agrees 

 with the thick posterior marginal ridge in fig. 5 (Bollia Hindei). 



Coll. Mr. J. M. Clarke, of Albany, X.Y. 



8. BoLLiA Hindei, sp. no v. (PI. XX. fig. 5.) 



Length 1'7 mm.; height 1 mm. 



This difi'ers from the typical Upper-Silurian Bollia hicollina, J. & 

 H., op. cit., in being relatively longer, in having a much thicker 

 marginal rim, a shorter and less open curve of its thick horse-shoe 

 lobe, and in having not only the anterior part of that lobe pinched 

 at its neck, but the hinder portion impressed with a strong oblique 

 furrow. B. interrupta, Jones, ojy. cit. vol. xix. p. 408, pi. xii. fig. 14, 

 presents an analogy in having its hinder lobe divided into two un- 

 equal parts, but the rest of the valve differs from our specimen. 

 The latter is from the Hamilton Group (Devonian), at Eighteen- 

 mile Creek, Lake Erie, New- York State (attached to a small Coral), 

 where also some of the Devonian Ostracoda described in the 

 Pebruary No. of the ' Quart. Journ. Geol. Soc' vol. xlvi., were ob- 

 tained. Coll. Dr. G. J. Hinde, P.G.S., after whom it is named. 



8*. Bollia ?, sp. (Not figured.) 



Length '64 mm. ; height '48 mm. 



A very small semicircular valve, rather rounder at one end than 

 at the other, somewhat undulate on the surface, with a faint curve 

 visible at the middle, as if it had been worn down from the curved 

 lobe of a Bollia. 



From the Devonian strata at Eighteen-mile Creek, Lake Erie, 

 N.Y. Coll. Dr. G. J. Hinde, P.G.S. 



Y. Streptjla, Jones and Holl, 1886. 



9. Steepijla TLANTAiiis, sp. nov. (PI. XX. figs. 8 a, Sh.) 



Length -88 mm. ; height '44 mm. 



This is one of the Strepulce with tortuous, and not merely loop- 



