446 CONTETBUTTONfi "PROM THE NATIONAL TIEK13AEIUM, 



-i 



Cypcrus tondazianus Bueck, Allgeiu. Bot. Zeitsclir. 1: 187, 1895. 



Distribution: Rather commoii in Europe, western Asia, and Africa; rare in 



America, 

 Costa Rican colt.ections: Hoffmann 190; San Jose, altitude 1,100 meters, Tonduz 



1532, 2832; San Francisco de Guadalupe, altitude 1,100 meters, Tonduz 1807. 



2. Pycreus propinquus^ Nees in Mart. FI. Cras. 2 ' : 7. 1842. 

 Cypmis propinquus Mart, and Schrad.; Nees, loc. cit., as synonym. 



Cypmis olfersianiis Kunth, Enmn. 2: 10. 1837. Not Pycreus olftrsianus Nees. 1842. 

 Distribution: Quite frequent in the wanner parts of Afri<'a and America. 

 Costa Rican collection: Caflas Gordas, altitudi* 1,100 meters^ Piiiier 11027. 



3. Pycreus helvus & 0. B. Clarke in Urb. Symb. Antill. 2: IG. 19. 1900. 

 Cypervs hu-mholdtianvs Schult. in Roem. & Schult. Syst. Mant. 2: 100. 1824. 

 Cy perv s helvus LiGhm. Dansk. Vid. Selsk. Skr. 2: 9. 1849. 



Distribution: Frequent in Mexico and Guatemala ; rare in snuthern Brazil and 



al)out Montevideo. 



Costa Rican collection: Turi'ialba, altitude 500 meters, Tond}f : S2()(]. 



Pycreus piceus, i. e. Cypcrus picais Liebm..^ is a species of the sc^ction Zonatae, not 

 very different from P. Jlaveseens Reichenb. 



4. Pycreus lagunetto (SteudO C. B. Clarke. 

 Cypcrus lagumiio Steud. Syn. PI. Cyp. 2: 5. 1855. 



Cypcrus aryeniinus C. B. Clarke, Journ, Linn. See. 21: 04. ISSI. 

 Annual, cespitose; umbel usually simple; spikelets 2 to C in each loose spike; glumes 

 chestnut-l)rown. pale on the back; style bifid; nut compressed laterally, puncticulale 



or subreticulate, not transversly lineolate. 



Stems 1 to 3 dm. long, rather slender. Leaves shorter than the stem, 2 to 3 mm. 

 wide. Spikelets commonly 12 mnu long, 8 to 12-flowered, occasionally as mucli as 25 

 mm. long and 32-flowered. Glumes somewhat turgid, slightly inflated (not rigid, much 

 flattened and indurated as in P. inclanostachyus and P. clegantula). Species differing 

 from P. rivularls by its loose inflorescence; perhaps rather to be regarded as a soufhcM-n 



form of that. 



Distribution : Rather frequent in Argentina, but in (ropical South America rare. 



Costa Rican collections: San Jose, altitude 1,100 meters, Tortduz 2,831; Rio 

 Agua Caliente, altitude 1,300 meters, Pitlief 2,404. 



5. Pycreus melanostachyus (IL B, K,) C. B. Clarke. 

 Cypcrus melanostachyus IL B. K. Nov. Gm. & Sp. 1: 207. 

 Cypcrus diandrus capitatus Brittou, Bull. Torr. Club 13: 205. 188G. 

 Cyper^ts iniricato-rav}nsi(s J\noc\i. Allgem. Bot. Zeitschr. 1: 186. 1895. 



Stem oblique at base; umbel almost crowded into a single head, or rarely (forma 

 ''umbcUifcra'^ Boeckl. ins.) looser, with rays 1 to 4 cm. long; spikelets 3 mm. wide, 

 linear-oblong, much flattened, rather hard, dark chestnut brown, almost black, shin 

 ing, glumes sharply carinate, rigidly imbricate (but compare var. ft below); styh^ 

 bilid; nut ellipsoidal, laterally compressed, obscurely puncticulate, not transversely 



lineolate. 



Distribution: Frequent from California to Argentina, very common in Mexico. 



Costa Rican collections: Hoffmann 207; Tres Rios, Pillicr 433(); Carrilh), alti- 

 tude 300 meters. Cooper 51-1; Akijuclita. altitude 1,000 m(4ers, Tondu: 078 l)is; La 

 Talma, altitude 1,500 meters, PtUicr C)78a, Tojidaz 12027; San Jose, altitu<le LlOO 

 meters, Tonduz :m)Cy, Alaju<4ita, altitud(M.,000 meters, T(mduzm47. 



5a. Pycreus melanostachyus variegata (H. B. K.) C. B. Clarke. 

 '■C7jpcrvs varicgatits 11. B. K. Nov. Gen. A Sp. 1: 208. 1815. 



«The specific name olfcrsiaiius is older and \moccupied. — Editor. 

 '^The specific name humholdtianus is older and unoccupi(*d. — Ei>itor 

 cDam:k. Vid. Selsk. Skr. 2; 12. 1849. 



