PLATE III. 



Fig. 1. — Leioptena Uirundo. An almost complete left valve. From the Carbo- 

 niferous Limestone of Castleton. My Collection. (Page 13.) 



Figs. 2, 3. — Leiopteria luimlata. Casts of tlie interior of left valves. From 

 the Shelly Limestone of Poolvash, Isle of Man. My Collection. (Page IL) 



Fig. A^.^Jjc'iopttena laminosa. — A left valve. From the Carboniferous Lime- 

 stone of Castleton, Derbyshire. (Page 14.) 



Fig. b.—Lciopter'ia laminosa. — A young specimen. From Hill Bolton, York- 

 shire. My Collection. (Page 14.) 



Fig. G. — Lciopicrld laminosa. The type of Phillips's (Jercillia lannnosa, pre- 

 served in the Gilbertson Collection, Natural History Museum, South Kensington. 

 (Page 14.) 



Fig. 7. — Leiopterla laminosa. A specimen from the Limestone of Lowick. In 

 theWoodwardian Museum, Cambridge. (Page 14.) 



Figs. 8, '^ .—Lciopteria laminosa. Two medium-sized specimens. From the 

 Cai'boniferous Limestone of Castleton, Derbyshire. My Collection. (Page 14.) 



Fig. 10. — Lriopferia, Thompso7ii. A full-grown specimen. From Hill Bolton, 

 Yorkshire. My Collection. (Page 17.) 



Fig. 11. — Lriiipteria Thompsoni. The cast of a left valve. Same locality and 

 Collection. (Page 17.) 



Fig. 12. — Leiopteria, granilis. The hinge-line and posterior part of a right valve. 

 From the Carboniferous Limestone of Castleton. My Collection. (Page 19.) 



Fig. 13. — Lpiopferia. (jrandis. The cast of the interior of the left valve. Same 

 locality and Collection. (Page 19.) 



Fig. 14. — Leiopteria, grandis. A full-grown example of a left valve. Same 

 locality and Collection. (Page 19.) 



Fig. 15. — Leiopteria grandis. Portion of the left valve. Same locality and 

 Collection. (Page 19.) 



