112 Annals of the Carnegie Museum. 



^ A. Dracontium (Linriceus). Green dragon. 



Sterrett Township, low woods near C C. Mellor's place, July, 

 1886. 



CALLA Linnaeus. 

 § C. palustris Linnaeus. Water arum. 



SPATHYEMA Rafinesque. 

 SYMPLOCARPUS Salisbury. 



* S. fcetida (Linnaeus). Skunk cabbage. 



ACORUS Linnceus. 



* A. Calamus Linnccus. Calamus-root. 



LEMNACE^ Dumortier. 

 DUCKWEED FAMILY. III-io. 

 LEMNA Linnaeus. 

 f L. minor Linnaeus. Lesser duckweed. 



f L, trisulca Linnaeus. Star duckweed. 



VALLISNERIACEiE Dumortier. 



TAPE-GRASS FAMILY. III-6. 



VALLISNERIA Linnteus. 



* V. spiralis Linnaeus. Tape-grass. 



O'Hara Township, Allegheny River above Aspinwall. Sejitember 

 20, 1899. 



ALISMACE^ De Candolle. 



WATER-PLANTAIN FAMILY. III-5. 



ALISMA Linnaeus. 



* A. Plantago-aquatica Linnaeus, ^^'ater-plantain. 



