234 Engelmann and Gray, 



not in sufficient abundance for distribution. It is a less hairy 

 plant. Under No. 306 we describe a fourth species, A. hu- 

 milis, which we also find in Drummond's second collection, 

 No. 230. The leaves in A. mercurialina, as in A. Drum- 

 mondii, often turn purplish, in drying. In No. 322 of Drum- 

 mond's third collection, the leaves are oblong-ovate, or ovate- 

 lanceolate, and often acute or acuminate, as in Lindheimer's 

 specimens. In No. 263 of the second collection they are 

 mostly ovate-orbicular. 



176. Tkagia urticjefolia, Michx. Houston, &c. April. 

 T. betonicaefolia, Nutt. 1 



177. Phyllanthus polygonoides, Nutt. (Maschalanthus, 

 Nutt. — Phyllanthus proper, Linn., Juss., etc.) Grassy banks. 

 July. 



178. Cnidoscolus stimulosus. = Jatropha stimulosa, 

 Linn. Houston. July. 



179. Urtica purpurascens, Nutt. in Trans. Amer. Phil. 

 Soc. (N. Set.) V. p. 169. Thickets, Galveston Island. 



180. Quercus virens, Ait. Moist woods along the 

 coast. 



181. Taxodium distichum, Rich. Houston, &c. 



182. Sagittaria simplex, Pursh. ? Ponds in clayey soil, 

 near Houston. June — September. Our plant has rather 

 rigid linear-lanceolate leaves ; the calyx as well as the ovate 

 acute bracts are a little pubescent ; the fertile flowers are on 

 short, the sterile on rather long peduncles ; the stamens from 

 20 to 30 ; and the carpels in fruit are compressed, rostrate, 

 and falcate. Larger specimens, collected near the coast, 

 with broader leaves, &c. bear larger flowers, with 40 to 50 

 stamens. 



183. S. stolonifera (n. sp.) : stolonibus radicantibus ; 

 foliis submersis lato-linearibus acutis, emersis lineari-lanceola- 

 tis 3-5-nerviis ; scapo simplici ; bracteis ovatis acutis vel 

 obtusiusculis brevibus ; pedunculis subternatis omnibus elon- 

 gatis ; staminibus 12-16; carpellis compressis oblique subor- 

 biculatis breviter mucronatis. — S. graminea, Nutt. in Trans. 



