15S GRAMINEAE 



Refs. — PoA GRACILLIMA Vasey, Contr. Nat. Herb. 1 : 272. 1S93. P. invaginata Scribn. & 

 Williams, U. S. Dept. Agr. Div. Agrost. Circ. 9: 6. 1899, type from "Summit Camp. Sierra 

 Nevada, July 10, 1870." 



22. P. unilateralis Soribn. Tufted perennial ; eiilnis 4 to 15 inches high ; 

 sheaths smooth, tawny and papery ; blades flat or folded, shorter than the 

 eulni.s ; panicle oblong, dense and spike-like, or somewhat interrupted below, 

 1 to 8 inches long ; spikelets 3 to 4 lines long, perfect ; glumes broad, acute, 

 smooth, indistinctly scabrous on keel near apex, the first 1-uerved or indis- 

 tinctly 3-nerved, the second 3-nerved; lemmas 2 lines long, not webbed at base 

 or pilose, scabrous on base of marginal nerves and apex of keel, the inter- 

 mediate nerves faint; palea ciliate on keels. 



C'lifi's, bluffs and rocky meadows near the seashore, numl)oldt Co. to ilon- 

 terey. 



Locs. — Ilumbolilt Bay, Chandler 1140; Mendocino, McMurphy 399; Pt. Arena, Dary tj- 

 JSlasdale 0024; Bodega Bay, Heller 5279; Pt. Reyes, Davy 6765, 6804, 6S81; San Francisco, 

 Abrams ir)99; Moutara Pt., Copeland 3306; Santa Cruz, Anderson; Monterey and vicinity, 

 Davy 7293, Helle'r 6702. 



Refs. — PoA UNILATERALIS Scribn.; Vasey, U. S. Dept. Agr. Div. Bot. Bull. 13=: pi. 85. 

 1893, type from San Francisco, Jones 15 in 18S2; Davy in Jepson, Fl. W. Mid. Cal. 67. 1901. 

 Atropis procvmhens Thurb. in Wats. Bot. Cal. 2: 309. 1880. This name is based on Poa 

 procumbens Curt, but the specimen in the Gray Herbarium ( Bolandcr 6467, seashore at Fort 

 Bragg, Mendocino Co.) cited by Thurber, consists mostly of Poa unilateralis and this is the 

 species described. But mounted with this is a fragment of Sderochlofl procumbens Beauv. 

 It is not impossible that this fragment may have been detached from a European specimen by 

 Dr. Thurber, for comparison with the Bolander specimen and not afterwanls removed. 

 Scleroehloa procnmbens is not known to grow on the Pacific Coast. 



23. P. thurberiana Vasey. Tufted perennial; culms 2 to 3 feet high, 

 smooth; sheaths somewhat scabrous, the basal smooth and papery; ligule 

 1 to 2 lines long; blades narrow, involute, scabrous; panicle narrow, 8 to 10 

 inches long, loose, the branches long, ascending; spikelets 2 lines long, 1 or 2- 

 flowered; glumes IV2 lines long, 3-nerved; lemmas li/i; lines long, scaberix- 

 lous, not pilose or webbed. 



Little known. Aside from the type collection b.y Lemmon, in Sierra Vallej', 

 this species was collected by Bolander (Los Angeles?) and what appears to be 

 the same species by Chase at Santa Barbara (no, 560-1). 



Refs. — Poa thurberiana Vasey, U. S. Dept. Agr. Div. Bot. Bull. 13=: pi. 84. 1893. Panic- 

 ularia thurberiana Kuntze, Rev. Gen. PI. 2: 783. 1891. Atropis paucifiora Thurb. in Wats. 

 Bot. Cal. 2: 310, 1880 (type from Sierra Valley, Lemmon). not Poo pauciflora Roem. & Schult. 

 1817. 



2-1. P. hanseni Scribn. Tufted perennial; culms erect, slender, 6 to S inches 

 high or sometimes taller, smooth; .sheaths smooth; ligule Y2 to 1 line long; 

 blades capillary, involute, smooth, mostly basal ; panicle narrow, 1 to 2 inches 

 long; spikelets 2 to 3 lines long; glumes ly^ to 2 lines long; lennnas scaberu- 

 lous but not pilose or web])ed. — Differs from P. pringlei in being more delicate 

 and in having smaller spikelets. 



A little known species from isolated localities in California. Modoc Nat. For., 

 Ilatfon 63; Plumas Co., IleUer 8751; Tuolumne :\Ieadows, Hall if- Babcock 3627 

 in part; Loma Prieta, Davy 53-lr. 



Ref.— Poa hanseni Scribn. U. S. Dept. Agr, Div, Agrost, Bull, 11: 53, pi, 9, 1898, type 

 from Silver Lake, Amador Co,, Hansen 605. 



25. P. idahoensis Beal. Tufted perennial ; culms slender, 6 to 18 inches 

 high, smootli. slightly scabrous below the panicle; sheaths loose and papery, 

 smooth; blades capillary, soft, scabrous, the basal as much as 10 inches long; 

 panicle narrow, contracted but loose, 1 to 2 inches long; spikelets 2V2 to 3 lines 



