398 The Ohio Naturalist. [Vol. XV, No. 2, 



Key to the Species. 

 1. Leaflets 1 pair. 2. 



1. Leaflets 2-6 pairs. 3. 



2. Stems wingless, flowers yellow. Lathyrus pratensis. (6). 



2. Stems winged, flowers usually purple to white. 4. 



3. Flowers purple. 5. 



.'3. Flowers yellowish-white. Lathyrus ochroleucus. (.5). 



4. Stems broadly winged glabrous, perennial. Lathyrus latif alius. (7). 



4. Stems narrowly winged, annual Lathyrus odoratus. (8). 



5. Stipules broad, foliaceous, regularly halberd shaped, leaflets ovate. 



Lathyrus maritimus. (1). 



5. Stipules narrow, half sagittate or wanting leaflets obovate. 6. 



6. Inflorescence with 10-20 flowers. Lathyrus venosiis. (2). 



6. Inflorescence with 2-6 flowers. 7. 



7. Leaflets linear or linear oblong, stems winged. Lathyrus palustris. (3). 

 7. Leaflets oblong or oval, stems wingless. Lathyrus myrtifolius. (4). 



1. Lathyrus maritimus (L) Bigel. Beach Pea. A glabrous 

 •climbing or erect perennial with a grooved angled stem, 1-2 ft. 

 high and % in. in diameter. Leaflets 2-6 pairs, oval, 1)2 in. long, 

 1 in. wide, tendrils branched, stipules broad, foliaceous, and 

 regularly halberd shaped. Peduncle shorter than the leaves; 

 flowers 6-10, racemose, purple, %-l in. long; pod glabrous, IjiS in. 

 long, Yi-ji in. wide, seeds 3-10, light brown. 



Ashtabula, Lake, Cuyahoga and Erie. It is also called 

 Sea-pea, Sea-side-pea and Everlasting-pea. 



2. Lathyrus venosus Muhl. Veiny Pea. A trailing or 

 climbing glabrous, or finely pubescent perennial, with a 4-angled 

 stem, 2-3 ft. long and }s in. in diameter. Leaflets 2-6 pairs, 

 obovate, 1-2 in. long, %,-! in. wide; tendrils compound, stipules 

 narrow, half sagittate or wanting. Peduncles shorter than the 

 leaves; flowers 10-20, 72-/8 in. long, purple; pod hnear, 1-3 in. long, 

 Ke-K in-, wide; seeds 3-8, brown. 



The Veiny Pea usually grows near rivers or lakes. Erie and 

 Williams. 



3. Lathyrus palustris L. Marsh Pea. A climbing, slightly 

 pubescent or glabrous perennial with an angled, usually winged 

 stem, 1-3 ft. long and Ke in. in diameter. Leaflets 2-6 pairs, 

 linear or linear oblong, 1-2)^ in. long, /8-/8 in. wide; tendrils 

 branched, stipules narrow, half sagittate or wanting. Flowers 

 2-6, ji in. long, purple; pod linear, 2-2% in. long, %-% in. wide, 

 the seeds 3-6, brown. 



The Marsh Pea is found in moist or wet soil. Lake, Cuyahoga, 

 Summit, Eric, Madison and Greene. It is also called Wild Pea. 



4. Lathyrus myrtifolius Muhl. Myrtle-leaf Marsh Pea. A 

 slender climbing, glabrous, or slightly pubescent perennial, with a 

 wingless, angled stem, 1-3 ft. long, and Xe in. in diameter. Leaflets 

 2-6 pairs, oblong or oval, 1-2 in. long, ji-ji in. wide; tendrils 

 branched ; stipules K-/8 in. long, narrow, half sagittate or wanting. 

 Flowers 2-6, purple, %-% in. long; pod linear, 2 in. long, Ke in. 

 wide, the seeds 3-8, brown. 



This species is found in moist or wet localities. Lake, Stark, 

 Erie, Lucas, Defiance and Auglaize. 



