382 MEMOIRS OF THE CARNEGIE MUSEUM. 



EXPLANATION OF PLATE XX. 



All figures are three-foufths natural size, a, lateral view; b, dorsal view. 



Fig. 1. Lampsilis fasciola Rafinesque. Male from Shenango River, Shenango, 

 Mercer Co., Pennsylvania, collected September 27, 1909; C. M. Cat. No. 6L4099. 



Fig. 2. Lampsilis fasciola Rafinesque. Gravid female from the Allegheny River, 

 Warren, Warren Co., Pennsylvania, collected September 15, 1909; C. M. Cat. No. 

 61.4019. 



Fig. 3. Lampsilis cariosa (Say). Very large male from the Chemung River, South 

 Waverly, Bradford Co., Pennsylvania, collected August 20, 1909; C. M. Cat. No. 61.4003. 



Fig. 4. Lampsilis cariosa (Say). Male of normal size from the Susquehanna 

 River, Duncannon, Perry Co., Pennsylvania, collected August 14, 1908; C. M. Cat. No. 

 61.3414. 



Fig. 5. Lampsilis cariosa (Say). Gravid female from the Susquehanna River, 

 Duncannon, Perry Co., Pennsylvania, collected August 14, 1908; C. M. Cat. No. 61.3414. 



Fig. 6. Lampsilis ochracea (Say). Probably male, judging from the shape, hardly 

 half-grown, from an unknown locality in the Hartman collection; C. M. Cat. No. 61.4437. 



Fig. 7. Lampsilis ochracea (Lea). Probably a female, judging from the shape, 

 hardly half-grown, from the Delaware River, Newbold, Gloucester Co., New Jersey, 

 collected by C. H. Conner; C. M. Cat. No. 61.4012. 



Fig. 8. Lampsilis orbiculata (Hildrefch). Half-grown male from the Allegheny 

 River, Godfrey, Armstrong Co., Pennsylvania, collected October 8, 1908; C. M. Cat. 

 No. 61.3504, 



