236 Engelmann and Gray, 



multo breviora. Stylus brevis (filamenta adaequans,) tenuis, 

 apice trilobus ; lobis bipartitis, partitionibus in stigmata filifor- 

 mia radiatim productis. 



EUSTYLIS. Perigonium hexaphyllo-partitum, confoime, 

 patens ; tubo nullo ; segmentis obovatis planis, tribus intcrio- 

 ribus modice minoribus. Filamenta distincta, e basi lato 

 subulata, antheras subpanduriformes post anthesin immutatas 

 sequantia : connectivum latum basi apicemque versus proeser- 

 tim dilatatum, loculis marginalibus. Stylus elongatus (stamina 

 adaequans,) ad apicem infundibuliformis, trifidus ; lobis bifidis, 

 partitionibus in stigmata filiformia recurvia attenuatis. — Habi- 

 tus, bulbus, capsula, etc., omnino Nemostylis. 



190. Gymnadenia nivea. (Orchis nivea, Nutt.) Moist 

 prairies near Houston ; April to June. The ovary remains 

 straight ; the labellum is therefore posterior. The outer lat- 

 eral divisions of the perianth are also produced at the base on 

 the upper side into a triangular blunt auricle, which is not 

 noticed in Nuttall's description. The anther-cells are parallel 

 and approximated. 



191. Spiranthes vernalis (n. sp.) : radice fasciculata ; 

 caule foliato ; foliis linearibus, superioribus sensim minoribus 

 vaginantibus lanceolato-subulatis ; sepalis petalisque basi co- 

 hserentibus oblongo-linearibus, lateralibus angustioribus label- 

 lum reflexum crenulatum apice non dilatatum aequantibus vel 

 superantibus. — Moist prairies, Galveston and Houston ; April, 

 May. — Stem 1 to 2 feet high, slender ; lower leaves often 5 to 

 6 inches long, 2 lines wide ; bracts ovate, acuminate. Flowers 

 much as in & cemua, from which it is distinguished by its 

 short lip, &c. 



192. Thalia dealbata, Fraser. Swamps on the Brazos; 

 September. — The seed appears to contain three embryos, of 

 which only the central one is fully developed. 



193. Juncus heteranthos, Nutt. in Trans. Amer. Phil. 

 Soc. (N. Ser.) V. p. 153. Galveston Island. May. 



194. PONTEDERIA LANCIFOLIA, Mulll. Jul)'. 



195. Smilax lanceolata, Linn. Rich shady soil near 



