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 gemis^ of which I am about to define se- 

 veral species, may be thus shortly distinguished from the 

 other genera of the Gentianeae, 



EXACUM, L. 



Sepale dorso carinato alata. Corolla rotata absque corona, circa 

 capsulam marcescens : sestivatio dextrorsum contorta. Glandulae 

 epipetalse vel hypogynse nuUae. Stamina 4 — 5 : anther ae immutatse 

 porro dehiscentes. Ovarium complete biloculare. Stylus filiformis 

 plus minusve adscendens. Stigma indivisum. Capsula valvulis in- 

 troflexis complete bilocularis, placentis demum utrinque liberis. 



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

 seen: 



Caules subsimplices, corymbi nudiusculi. 



Stamina 4 E. tetragomim, R. 



Stamina 5. 



Folia ovalia acuta yix acuminata CO- 1 e. macranthum, Am. 



rollae lacnnje ovali-oblongse acutae... J 

 Folia lanceolata utrinque attenuata "| 



subundulata. corollas lacinise obovales \ E. ceylanicum, L. 



obtusiusculae J 



Caules valde ramosi. 



Stamina 5 : inflorescentia foliosa. 



Caules ramique late 4-alati : capsula glo- ^ ^ Wightianum, Am. 

 boso-ellipsoulea : liores magni J ^ 



Caules ramique 4-goni vix alati : flores parvuli. 



Folia oblongo-lanceolata acuminata : "| 



cor. laciniae obovatas ; capsula ovata V E. courtallense, Arn. 



oblonga J 



Folia ovata acuta : cor. laciniae ob- "j 



longo-lanceolatEe : capsula oblongo- > E. Walkeri, Arn. 



ellipsoidea J 



Stamina 4: inflorescentia nudiuscula : cap- "1 E.pedunculaium.h. 

 sula globosa ; nores 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- 

 libus, corymbo nudiusculo, coroUse laciniis 4 oblongis acutis, pe- 

 dunculis fructiferis rectiusculis. 



Hob. ad oras Malabaricas. 

 Flores mediocres. 



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

 liis subpetiolatis ovalibus acutis vix acuminatis, corymbo nudi- 



