206 CALIFORNIA ACADEMY OF SCIENCES. 



§ Piptocalyx. 



X. circumscissa, Gray. 



Depressed and diffusely branched: leaves alternate: spikes 

 short, glomerate: nutlets a half line long, light gray, mi- 

 nutely puncticulate, ventral suture divaricate-forked at base. 

 Proc. Am. Acad. xx. 275. 



Ranging from Washington Territory to the Southern part 

 of California, and eastward in Nevada. The plant of Ne- 

 vada and California is many times larger than the original 

 Lithospennum circumscissum, H. & A. of the far north, and 

 has a very different pubescence, but the light gray puncticu- 

 late nutlets are everywhere the same, and so it may not be 

 well to separate these two; but the following is very distinct 

 namely: 



X. dichotoma. 



Erect and dichotomously branching, 2 — 6 inches high: 

 leaves opposite: calyces in the forks of the branches, and 

 along the internodes where they are subtended by a solitary 

 bract : nutlets twice as long as in the last, but not thicker, 

 acuminate, light brown with darker spots, very smooth and 

 shining, basal forking of ventral groove short and not divari- 

 cate. 



Eastern base of the Sierra Nevada, between Boca and 

 Verdi, 1884; Mrs. Curran. 



These plants, with their peculiar habit and circumscissile 

 calyx, appear to call for that subgeneric rank, even in 

 Krynitzlda, which was accorded to Dr. Torrey's Plptocalyx 

 in the Botany of California. 



§ Pterygium, Gray, 1. c. in part. 



* Nutlets winged, 



X, pterocarya, Gray, 1. c. in part. 



One nutlet of the 4 commonly wingless: wings of the 



