88 Dr. Arnott on some new or rare Indian Plants, 



and by the one-celled or at most imperfectly two-celled cap- 

 sule. The Asiatic genus, of which I am about to define se- 

 veral species, may be thus shortly distinguished from the 

 other genera of the Gentianece. 



EXACUM, L. 



Sepale dorso carinato alata. Corolla rotata absque corona, circa 

 capsulam marcescens : aestivatio dextrorsum contorta. Glandulse 

 epipetalse vel hypogynse nuUae. Stamina 4 — 5 : antherse immutatae 

 porro dehiscentes. Ovarium complete biloculare. Stylus filiformis 

 phis minusve adscendens. Stigma indivisum. Capsula valvulis in- 

 troflexis complete bilocularis, placentis demum utrinque Hberis. 



The following is a Clavis Analytica of all the species I have 

 seen : 



Caules subsimplices, corymbi nudiusculi. 



Stamina 4 E. tetragonum, R. 



Stamina 5. 



Folia ovalia acuta vix acuminata, co-"! r, ,, , 



11 I • • T 11 I r Jc^. macranthum. Arn. 



rollae lacmise ovali-oblongse acutae... J ' 



Folia lanceolata utrinque attenuata "j 

 subundulata. coroUselaciniaeobovales I E. ceylanicum, L. 

 obtusiusculae J 



Caules valde raniosi. 



Stamina 5 : inflorescentia foliosa. 



Caules ramique late 4-alati ; capsula fflo- 1 ,, nr- i j- « 



1 11- ^ J a • ^ > L, Wiqhtianum. Arn. 

 boso-ellipsoidea : rlores magni J -^ ' 



Caules ramique 4-goni vix alati : flores parvuli. 



Folia oblongo-lanceolata acuminata : "| 



cor. laciniae obovatag ; capsula ovata I E. courtallense, Arn. 



oblonga J 



Folia ovata acuta : cor. laciniae ob- "| 



longo-lauceolatae ; capsula oblongo- v E. Walkeri, Arn. 



ellipsoidea J 



Stamina 4: inflorescentia nudiuscula : cap- | e. pednnculafum, L. 

 sula globosa : flores parvi j ^ ' 



These may be more perfectly defined as follows : 



1. E. tetragonum (Roxb.) caulibus subsimplicibus basi 4-alatis 

 sursum 4-angulatis, foliis ovalibus vel oblongo-lanceolatis sessi- 

 hbus, corymbo nudiusculo, corollse laciniis 4 oblongis acutis, pe- 

 dunculis fructiferis rectiusculis. 



Hab. ad oras Malabaricas. 

 Flores mediocres. 



2. E. macranthum (Arn.) caulibus subsimplicibus teretiusculis, fo- 

 liis subpetiolatis ovalibus acutis vix acuminatis, corymbo nudi- 



