4 THE OKNUS MANETTTA 



Achille Richard (1S20) in "his Memoire sur la famiUe des 

 Ruhiacees (Mem. Soc. Hist. Nat. Paris, v.) has left a contribution to 

 the history of the genus that is rather curious than important. Nacihea 

 and Manettia he unites, with several other genera or parts of genera 

 under Bouvardia. Nacihea alba is, however, reserved as a separate 

 monotypic genus, which he calls Conotrichia, distinguished by the 

 obscurely toothed calj^x {obsolete 4i-dentatus), the short, almost 

 globose corolla, and the cone of hairs that surmounts the throat. A 

 series of excellent figures accompanies Richard's description (t. 14. 

 f . 1) ; and should the question of raising the sections of Manettia to 

 generic rank be urged, Conotrichia would undoubtedly have strong 

 claims for its characters if not for its name. For the present, how- 

 ever, it may be regarded as linked to the Lygistum-group by way of 

 several species (see Systematic Account). 



We have now traced the history through the descriptions of the 

 first-known species of each of the four sections of Manettia as arranged 

 by Schumann in the Flora Brasiliensis (infra) ; namely Ltgistum, 

 the first of all ; Ysgina>'THUS, the type of Manettia itself ; Pyk- 

 RHANTHOS, introduced by Martins in 1824— ilfl cordifolia ; and 

 Heteeochloba, represented first in 1825 by Vellozo's Gtiagnebina 

 Inteo-rubra. In 1850, with the recognition of the identity of 

 Guagnebina and Manettia, we have the latter genus constituted as 

 it stands at the present day, wath all its sjnionyms recognized by each 

 of the principal systematists in turn. 



The subsecpient literary history is, comparatively speaking, un- 

 important, involving no more than the publication of new species, 

 without question of the authenticity of the genus. 



The late Karl Schumann's contribution in Flora Brasiliensis, vi. 

 vi. 167, while leaving much to be desired in its details, is of value, 

 because of his primary division of the genus into four sections. These 

 are well niarked each from the rest, and are readily recognizable by 

 means of the following characters : — 



I. § Ptrehantiios K. Schum. Manettia Mart. Corolla clavate 

 elongated, rarely less than 3 cm. in length, generally much larger; 

 gradually, but not much, widened fi-om the base upwards. Limb 

 usually spreading, relatively very small. Corolla quite glabrous ex- 

 ternally, except in two species. 



This section includes, of the species as arranged in the present 

 study, new species being marked with an asterisk-: — 



domingensis Sprague. 

 Tiveedieana K. Schum. 

 gracilis K. Schum. 

 *Burchellii Wernham. 



cordifolia Mart. 

 *holiviana Wernham. 



chrysodertna Sprague. 

 *stipulosa Wernham. 



*sublanata Wernham. 



zimnpanica Hemsl. 



pubescens Cham. & Schl. 

 *angustifolia Wernham. 



II. § Heteeochloba K. Schum. Guagnebina Veil, in part. 

 Flowers of medium size. Corolla with stout tube upwards of 2 cm. in 

 length, subcylindrical, or inflated at the base and gradually narrowed 

 upwai'ds, or sometimes inflated toward the mouth. Limb very small, 

 the short lobes more or less erect. Corolla densely tomentose ex- 

 ternally. 



