MACLOSKIE I REVISION OF FLORA PATAGONICA. 55 



Add Macl., p. 226 : 



P. DUSENII Hack., apud Dusen, Neue Gefasspfl., Patag., p. 8, 

 Taf. 3, Fig. i, and Taf. 7, Fig. 3. 



Perennis, caespitosa, innovationibus intravaginalibus ; culmi erecti, c. 35 

 cm. alti, subcompressi, glaberrimi, uninodes, nodo parum supra basin sito 

 denudato, superne longi nudi ; vaginae culmeae compressae, glaberrimae, 

 summa 10-12 cm. longa, laminam brevem ferens, infimae, praesertim inno- 

 vationum, valde dilatatae, subbulbosae, emortuae cinereo-fuscae, diu pcr- 

 sistentes ; ligula foliorum innovationum elongata (6-8 mm. longa), sub- 

 tubulosa, hyalina, glabra, foliorum culmeorum brevior, in vaginae margines 

 late decurrens ; laminae innovationum arete setaceo-complicatae, c. 6 cm. 

 longae, 0.5 mm. diam., culmeae breviores, latiores, omnes erectae, glauco- 

 virides, glaberrimae, lateribus (in sicco) sulcatae ; panicula lineari-oblonga, 

 6-9 cm. longa, contracta, c. 1.5 cm. lata, densa, rachi ramisque laevibus, 

 his binis-ternis, erectis, rigidulis, primario inferiore 2-3 cm. longo, in # 

 inferiore nudo, multospiculato, secundario brevi, fere a basi spiculifero, 

 plurispiculato, spiculis breviter vel brevissime pedicellatis, pediccllis 

 scabris, subaequaliter et dense imbricatis ; spiculae fcemineae tantum note, 

 ovato-oblongae, dense 4-5-florae, ad 7 mm. longae, floribus sese fere ad 

 apicem usque tegentibus, ex albo-viridulo et livide violaceo-variegatae ; 

 glumae steriles subaequales, 5-6 mm. longae, ovato-lanceolatae, acuminatae, 

 acutissimae, 3-nerves, carina superne scabra, fertiles fere ad apicem usque 

 tegentes, ovato-lanceolatae, acutae, 5 mm. longae, in # vel J^ superiore 

 albo-membranaceae, glabrae, nervo medio tantum percursae, in % -ft infe- 

 riore omnino dense appresseque pilosae, 5-nerves (nervis in pute immersis), 

 callo brevissime pilosulo (neque crispato-lanato) ; palea quam gluma # 

 brevior, lanceolata, acute bidentula, carinis in ]/ 3 inferiore villosulis; 

 stamina non inveni ; caryopsis oblonga, subtrigona glumae laxius, paleae 

 arctius adhaerens. 



E. Patagonia, by Puerto Mazaredo on bushy steppe. 



This species belongs probably to the section Dioicopoa. The description 

 of Poa pubiflora Benth. shows that a very close relation exists between 

 that species and the present. P. pubiflora is denoted by "palea inferior 

 undique molliter pubescens et carina longiuscule ciliata," while in P. 

 Dusenii the floral glume is hairy only in its lower part and its carina 

 scarcely ciliate. Bentham's brief diagnosis gives no statement about the 

 ligule which, therefore, must be presumed not to show any conspicuous 



