collected by Mr. Schomburgk in British Guiana. 443 



SCliOPHULARlACEiE. 



49. Bacopa aquatica. Aubl. PI. Guian. i. p. 128. t. 49. Herpestis 

 stellarioides /3 Cayennensis. Benth. in Hook. Comp. Bot. Mag. ii. p. 57. 

 — Swampy situations on the Essequibo and Rupunoony. Schomburgk, n. 

 532. — French Guiana. Leprieur and Herb. Par. n. 178. . 



This remarkable genus is so exactly a Herpestis in everything but 

 the stamina, that in my enumeration of the genus Herpestis, having 

 a meagre Cayenne specimen before me, without corolla or stamina, 

 there did not appear to me to be any decided character to distinguish 

 it even as a species from the H. stellarioides ; and I had excluded 

 Bacopa from the order on account of the regular pentandrous flowers. 

 Having now, however, had opportunities of examining good flowers, 

 I am convinced that it is one of those plants which show that the 

 absence or sterility of the fifth stamen is not an essential character 

 of the ScrophulariacetE, and Bacopa must take its place next to Her- 

 pestis in my tribe of Gratiolece. The following are the generic and 

 specific characters I should propose : — 



Calyx 5-partitus sepalis imbricativis, postico maximo foliaceo, 2 anticis 

 pariter foliaceis at minoribus, 2 lateralibus interioribus lineari-carinatis. 

 Corollas ubrotata v. campanulata, aequaliter 5-fida, aestivatione imbrica- 

 tiva. Stamina 5, aequalia, laciniis corollinis alternantia. Anthera? lineari- 

 sagittata?,biloculares, loculis subparallelis, rima longitudinali dehiscenti- 

 bus. Ovarium biloculare. Stylus simplex. Stigma bilamellatum. Capsula 

 membranacea, vix dehiscens, bilocularis, dissepimento membranaceo fere 

 per totam superficiem placentifero. Semina numerosissima, horizontalia, 

 oblongo-ovoidea, acuminata, testa reticulata, albumine copioso, em- 

 bryone crassiusculo recto, radicula ad hilum spectante. — Herba? Ame- 

 rican tropica?, paludosae, glabra?, Herpestidibus pluribus sectionis Bramiee 

 similes. Folia opposita. Pedunculi axillares, solitarii vel fasciculati, 

 uniflori, bracteis 2 setaceis aucti. Corolla? coerulescentes v. alba?. 



1. B. aquatica (Aubl.), foliis lanceolatis, bracteis a calyce remotis, sepalis 

 exterioribus in pedunculum subdecurrentibus, corolla? calycem subdimidio 

 superantis laciniis ovali-oblongis. 



2. B. grandiflora (Mart.), foliis lanceolatis, bracteis calyci approximatis, 

 sepalo postico basi cordato, corolla? calycem duplo superantis laciniis late 

 obovatis. — In inundatis et aquis stagnantibus inter Alegre et Olho d'Agoa, 

 in provincia Brasilia? Piauhi inferiori legit cl. Martius. 



50. Herpestis sessiliflora. Benth. in Hook. Comp. Bot. Mag. ii. p. 58. 

 — French Guiana. Leprieur and Herb. Par. n. 180. 



51. Beyrichia ocimoides. Cham, et Schlecht. Linnaea, iii. p. 21. — Sands 

 of the Essequibo and Rupunoony. Schomburgk, n. 528. 



52. Conobea aquatica. Aubl. PI. Guian. ii. p. 639. t. 258. — Demerara. 

 C. S. Parker.— French Guiana. Leprieur and Herb. Par. n. 179. 



53. Vandellia Crustacea. Benth. Scroph. Ind. p. 35. — French Guiana. 

 Herb. Par. n. 177, 



