PLATAXACEAE 



143 



4. Ribes floridum L'Her. Wild Black Currant. 

 Along water courses throughout the state. Antelope County; Arapa- 

 hoe; Aten; Bellevue; Burwell; Holdrege; Lincoln; Norway; Sioux 

 County. 



5. Ribes inebrians Lindl. 



On dry hills in the northwestern part of the state. Banner County; 

 Belmont; Harrison; Sioux County. 



6. Ribes aureum Pursh. 



Common on the hillsides in the western and northern parts of the 



state. Belmont; Lincoln; Mullen; Xew Helena; Ft. Robinson; Sioux 



County. 



6a. Ribes aureum chysococcos Rydb. 



Rare in the northwestern part of the state. Banner County; Cherry 



County; Scotts Bluff County. 



5. PLATANACEAE. 

 Platanus. 490. 



1. Platanus occidentalis L. Button-Ball, Plane-Tree. 



In low woods in the southeastern part of the state. Brownsville; 

 Peru; Richardson County. 



MYRTALES. 



Terrestrial plants, or if aquatic the submerged leaves neither whorled 

 nor dissected. 

 Hypanthium enclosing the ovary but free from it. 1. Lythraceae. 

 Hypanthium adhering to the ovary. 



Flowers usually with petals, leaves rarely cordate. 



2. Onagraceae. 

 Flowers apetalous; leaves broader than long, cordate. 



5. Aristolochiaceae. 

 Aquatic plants with whorled leaves. 



Submerged leaves pinnately dissected. 3. Halorrhagidaceae. 



All the leaves entire. 4. Hippuridaceae. 



1. LYTHRACEAE. 



Hypanthium short, about as long as wide. 

 Leaves, at least the upper, clasping by a broad auricled base. 



1. Ammannia. 

 Leaves not auricled, usually narrowed at the base. 



Calyx without accessory teeth in the sinuses; petals none. 



2. Didlphis. 

 Calyx 4-toothed with as many accessory teeth in the sinuses; 

 petals 4, small. 3. Rotala. 



Hypanthium cylindrical, much longer than wide; petals generally 6. 



4. Lythrum. 



1. Ammannia. 648. 



Flowers axillary, sessile or nearly so. 1. A. coccinea. 



Flowers in axillary cymes pedicels 1-3 mm. long. 2. A. auriculata. 



