438 



NATURAL HISTORY OF PLANTS. 



Hiriea [Mascagnin) dcrjansi 



^^T\,.^ 



>iV 



'% 



-^-# 



#' 



III. HIE^A SERIES. 



Whilst in tlie plants of the preceding series, the wings bearing 

 the carjjels are dorsal {NoiopterygiecB)^ in these they are lateral 

 {Pleuropterygica').! or at least that is most usually the case (without 

 however the development of the dorsal wing being constantly want- 

 ing). The flower presents no fundamental 

 difference to that of Malpighia or Banisteria. 

 In Tlirwa ' itself, for example, there are five 

 sepals, bearing eight or ten glands, or, more 

 rarely, without glands, five uncut petals, two 

 vertieels of five stamens, three carpels with 

 uniovulate ovaries and short truncate styline 

 branches ; and the fruit is formed of one to 

 three samarte (fig. 441), whose dorsal wing is 

 wanting or but slightly developed, the edges 



Fig. 441. Eipe carpel. . °. . . .° 



being dilated m tAVO large reticulate winga 

 which are even joined more or less completely 

 above and below, so as often to form only one peltate and veined 

 surface. Hirwa consists of shrubs, often climbing, of tropical 

 America, where about fifty specie^ ^ are enumerated. They have 

 opposite leaves, and flowers^ collected in clusters or axillary corymbs, 

 more or less ramified and composed of cymes, with articulate floral 

 pedicels, sessile or not, and bearing two opposite bractlets in the 

 upper part.* 



Close beside Ilircca are placed Diphptcrys^ Tctrapterys, and Triop- 

 terys, also belonging to the warm regions of America. Diploptcrys 

 has sepals without glands and petals fimbriate on the edges. The 

 samaras have five wings, the least having generally the shape of a 

 short vertical ridge, whilst the lateral, confluent above and below, 



form two thick plates towards 



each edge. 



Tetrapterys has usually 



' Jacq. Stirp. Jmer. 137, t. 176, fig. 42.— 

 DC. Prodr. i. 586 (part.). — A. Juss. Ma/pigh. 

 294, t. 19.— Spach, Sidt. d Buffon, iii. 139.— 

 Enbl. Oeii. n. oo68.— B. H. Gen. 260, n. 40.— 

 H. Bn. Payer Fam. Kat. 312. 



- H. B. K. Nov. Gen. et Spec. v. 169.— A. Jrss. 

 in A. S. S.FLBras. Mcr. iii. 13, 1. 164.— Griseh. 

 Liiuiaa, xiii. 239 ; Mart. PI. Bras. Malpigh. 98, 



t. 20.— Tr. et Pl. Ann. Sc. Nat. ser. 5, xviii. 

 326.— Wai.p. Rep. v. 320 ; Ami. i. 131 ; ii. 205 

 iv. 370; vii. 474. 



' Yellow, rosy or lilac. 



■• Two sections are distinguished : 1° Eiihirira 

 {Uirrea A. Juss.) ; 2" Mascagnia (Bert, ex (Jot.l. 

 Hort. Bip. 86. — Griseb. PL Brit. TF.-Ind. 121 ; 

 PL Bras. 89, t. 18, 19. 



