collected by Mr. Schomburgk in British Guiana. 443 



SCROPHULARIACEiE. 



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

 stellarioides /3 Cayennensis. Bentk. in Hook. Camp. Hot. 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 Scrophulariacece, 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 

 pari(er foliaceis at minoribus, 2 lateralibus iuterioribus lineari-carinatis. 

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

 tiva. Staminas, aequalia, laciniis coroUinis alternantia. Antherae lineari- 

 sagittatse,biloculare3, loculis subparallelis, rima longitudinali dehiscenti- 

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

 membranacea, vix dehiscens, bilocularis, dissepiment© membranaceo fere 

 per totam superficiem placentifero. Semina numerosissima, horizontalia, 

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

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

 ricse tropicse, paludosje, glabrae, Herpestidibus pluribus sectionis Bramice 

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

 unifiori, bracteis 2 setaceis aucti. Corollas ccenilescentes v. albse. 



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

 exterioribus in pedunculum subdecurrentibus, coroUse calycem subdimidio 

 superantis laciniis ovali-oblongis. 



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

 sepalo postico basi cordato, coroUae calycem duplo superantis laciniis late 

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

 in provincia Brasiliae Piauhi inferiori legit cl. Martins. 



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

 — French Guiana. Leprieur and Herb. Par. n. 1 80. 



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. 



