CATALOGUE. 165 



Thelesperma gracilis, Gray. — Erect, much branched above, smooth; 

 leaves pinnately 5-7-parted, the divisions linear and somewhat rigid ; heads 

 hemispherical, on peduncles 4-6' long; outer series of involucral scales 

 obtuse or acutish; inner series acutish, with margin slightly, if at all, 

 scarious; rays none. ("Achenia oblong-linear, crowned with two stout sub- 

 ulate persistent spreading retrorsely pectinate-hispid awns." — Porter and 

 Coulter in Fl. Col. p. 72.) — Arizona, Loew. 



Cosmos* bipinnatus, Cav., var. parviplorus, Gray. {Cosmos parvi- 

 Jiorus, H. B. K.) — Annual, erect, 6-12' high, glabrous, leafy ; leaves petioled 

 bipinnately parted; segments narrowly linear or capillary; outer series 

 of involucral scales lanceolate, acuminate, as long as or exceeding the 

 inner, obtuse, and somewhat scarious-margined ones ; outer achenia short, 

 and the inner ones somewhat longer-beaked; awns variable in number, 

 2-4. — Arizona (639) and New Mexico. 



Bidens tendisecta, Gray. — Annual, glabrous, branching from the base, 

 leafy ; leaves bipinnately parted ; segments entire (rarely again divided) and 

 lanceolate ; scales of the involucre linear, hirsute, especially at base ; rays 

 (4-7) hardly exceeding the disk; "achenia attenuate-linear, glabrous sub- 

 tetragonal" ; awns nearly as long as the achenia and very strongly down- 

 wardly barbed. — Colorado, in the Arkansas Valley (544). 



Bidens foeniculifolia, DC. — Tall, branching, glabrous, or with the 

 youngest branches puberulent ; leaves 2-3 times pinnately divided ; seg- 

 ments entire or sometimes lobed ; involucre with the outer scales linear, 

 ciliate, and nearly as long as the inner ones, which are oval, with yellowish, 

 scarious margins ; rays large, 5-6, 8 -/ long, oval, deep yellow, with plain, 

 brown veins. Achenia (I have not seen) given by Dr. Gray in PI. Wright. 

 2, p. 90, as 2J lines long (the "vai. acheniis minoribus"), and by DC. Prod. 

 v, p. 603, as 3-3J lines long, and linear-tetragonal, hardly scabrous at the 

 apex, 2-awned. — Sanoita Valley, Southern Arizona (671). 



Bidens heterophylla, Ort. 1 var.? — Erect, smooth; lower leaves 

 petioled, pinnately " 5-7-parted" ; segments distant, linear, entire, the terminal 



* Cosmos, Cav. — Differs from Thelesperma in the inner series of involucral scales not being connate 

 to or above tiie middle and the rays being rose- or violet-colored, and from Bidens in the achenia being 

 more or less rostrate at the apex. 



