ORCHIDACEM 63 



A DESCRIPTIYE LIST OF ORCHIDACEOUS 

 PLANTS COLLECTED IN THE PHILIPPINE 

 ISLANDS BY BOTANISTS OF THE UNITED 

 STATES GOVERNMENT 



PAPHIOPEDILUM, Pfitzer ^ 



P. Argus, Pfitzer in Engler's Bot. Jahrb. 19 : 40 (1894). — 

 Cypripedium Argus, Rchb., f ., Gard. Chr. 1873, 608 : " (Corii- 

 folia tessellata.) Pedunculo elongato ; bractea ovarium longe non 

 aequante; sepalo supremo impari a basi late oblonge triangulo, 

 sepalis lateralibus connatis acutis labello bene brevioribus ; tepa- 

 lis ligulatis obtuse acutis porrecto divaricatis ciliatis ; labelli sacco 

 juxta ostium retusum utrinque angulato ; staminodio semiorbicu- 

 lari antice retuso medio apiculato utrinque argute unidentato." 



Leaves elliptic or oblong-lanceolate, distichous, radical, 12-20 

 cm. long, pale green, variegated with dark green. Scape erect, 

 pubescent, madder-purple, 3-4 dm. high. Ovary subtended by 

 a ciliate bract 2.5 cm. long. Flowers 6-8 cm. in vertical diameter. 

 Upper sepal broadly ovate, white, veined with green, often finely 

 spotted near the base, margin ciliolate. Lower sepals coherent, 

 smaller than the upper one. Petals slightly deflexed, oblong, 

 about 5 cm. in length, 1 cm. wide, whitish at base, veined with 

 green, madder-purple near the apex, spotted, margins ciliate. Lip 

 inversely helmet-shaped, 3.5 cm. long. Staminodium crescent- 

 shaped, with a tooth midway between the strongly incurved horns. 



Closely aUied to P. ciliolare, Pfitzer, from which species it may 

 readily be distinguished by its petals' being spotted nearly to the 

 apex. The petals of P. ciliolare are rarely spotted on the apical 

 third. 



1 Genera follow sequence adopted by Engler & Prantl. 



