24 FLORA OF PHILADELPHIA. 



3. ZANNICHELLIA L. Horned Pondweed. 



1. Zannichellia paltjstris L. M. p. 50. Fresh or brackish ponds. Sum- 

 mer. 

 Bucks— Andalusia, Mart. (Fr.). Delaware— Tinicum, T. C. Palmer (Fu.). 

 Ocean— Forked River (Cr.) (Ja.). 

 New Castle— Port Penn, Brandywine Creek, East Channel. 



4.NAIAS L. Naiad. 



1. Naias flexilis (Willd.) Rost. & Schmidt. M. p. 51. Ponds and slow 

 streams. Summer. 

 Bucks— Sellersville (Fr.). Delaware— Valley of Darby Creek (B. Sm.). 

 Chester— (P.). Lancaster— Susquehanna opposite Marietta (Le.). North- 

 ampton— Saylor Lake, Wind Gap (He.). ' 



Camden— Delaware River, Camden, Mart. (B. C). Gloucester — Re- 

 paupo Meadows (He.), Big Timber Creek (Li.). 

 New Castle— Common. 



5. ZOSTBRA L. 



1. Zostera marina L. Grass-wrack, Eel-grass. M. p. 51. Shoal water of 

 bays along coast. Summer. 



Family 2. SCHEUCHZERIAOEAE Agardh. 

 Leaves all basal; flowers numerous, in a spike-like raceme. 1. Triglochin. 

 Stem leafy; flowers few in a loose raceme. 2. Scheuchzeria. 



1. TRIGLOCHIN L. Arrow-Grass. 



1. Triglochin maritima L. M. p. 52. Salt marshes. Summer. 

 Ocean — Point Pleasant (Bri) (Ja.). 



2. SCHEUCHZERIA L. 



1. Scheuchzeria paltjstris L- M. p. 53. Bogs. Summer. 

 Bucks— Rock Hill (Cr.). 

 Camden— Longacoming (C). Gloucester— Repaupo. 



Family 3. ALISMACEAE DC. Water Plantain Family. 



Carpels in a ring upon a small, flat receptacle; 1. Alisma. 



Carpels crowded in many series upon a large convex receptacle. 



Flowers perfect, staminate or polygamous. 2. Lophotocarpus. 



Flowers monoecious or dicecious. 3. Sagittaria. 



1. ALISMA L. ■ 



1. Alisma Plantago-aquatica L. Water Plantain. M. p. 54. Shallow 

 water and ditches. Summer. 



2. LOPHOTOCARPUS T: Durand. 



1. Lophotocarpus calycinus (Engelm.) J. G. Smith. M. p. 55. Swamps. 

 Summer. 

 New Castle— Shelpot Creek, Delaware City, Augustine Pier. 



