CATALOGUE. 165 



Tiielesperma 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. parviflorus, Gray. (Cosmos parvi- 

 florus, II. 13. 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 longei'-beaked ; awns variable in number, 

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



Bidens tenuisecta, 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 fceniculifolia, 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 2£ lines long (the "vai. acheniis minoribus^), and by DC. Prod, 

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

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



Bidens heteropiiylla, 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 conuato 

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

 more or less rostrato at tho apex. 



