180 PROCEEDINGS OF THE AMERICAN ACADEMY 



1875. The few specimens are imperfect, only a few perhaps unde- 

 veloped flowers remaining on the receptacles. 

 * Trifolium Brandegei. Dwarf, perennial, cespitose and acau- 



the tube : small solitary fertile flowers often borne under ground. — Louisiana 

 to Texas. 



25. T. Bejariense, Moricand. Slightly hairy: calyx herbaceous, unequally 

 lobed, nearly equalling the corolla ; upper tooth nearly distinct, narrow ; the 

 rest broad, acute, reticulated : standard and wings broad, toothed, 3 lines long. 

 — PI. Nouv. 2, t. 2. T. macrocalyx, Hook. Ic. PI. t. 275. Texas. ' 



§ 4. Leaflets 3 : heads subtended by a mostly nionophyllous usually many-cleft 

 involucre, axillary : flowers in whorls, sessile or nearly so, not reflexed. 



* Low or dwarf perennials, acaulescent or nearly so : flowers rather large : 

 involucre parted, somewhat scarious. — Rocky Mountains. 



26. T. Parry I, Gray. Glabrous, often stout: leaflets oblong to oblanceo- 

 late : flowers large, in close heads : bracts 5 to 7, oblong, obtuse : calyx-teeth 

 broadly subulate, equalling the tube. — Am. Jour. Sci. 2. 33. 409. 



27. T. DASYPHTLLUM, Torr. & Gray. Cespitose, silky : leaflets linear-lan- 

 ceolate, entire : bracts very small, unequal, lanceolate : teeth linear, much longer 

 than the tube. 



28. T. Anuinum, Nutt. Cespitose, silky : leaflets cuneate-oblong, entire : 

 involucre of 2 broadly stipuled 3-foliolate leaves : teeth subulate, nearly equal- 

 ling the smaller flowers. — Watson, Bot. King's Rep. 60, t. 8. 



* * Slender annuals : corolla not becoming inflated. — Western. 



•4- Involucre not membranaceous, deeply lobed : lobes laciniately and sharply 

 toothed. 



29. T. ixvoLUCRATUM, Willd. Glabrous: leaflets mostly oblanceolate, acute 

 at each end : flowers I inch long, in close heads : teeth thin, long and narrow, 

 entire : ovules several. — T. Wormskioldii, Lehm. T. fimbriatum, Lindl. T. 

 spinnlosum, Dougl. From British America to Mexico. 



Var. HETERODOX. Heads mostly larger and leaflets broader: some of the 

 teeth setaceously cleft. — T. heterodon, Torr. & Gray. Washington Territory to 

 New Mexico. 



30. T. TRiDENTATUM, Lindl. Smooth or glandular-puberulent : leaflets 

 linear to narrowly lanceolate : flowers 6 to 8 lines long in close heads : teeth 

 rigid, rather abruptly narrowed from a broad base into the spinulose apex, 

 entire or shortly toothed : ovules 2. — T. involucrattim, Torr. & Gray. T. acicu- 

 lare & poli/pliiflliun, Nutt. From Washington Territory to S. California. 



Var. OBTUSIFLORUM. Stouter, often glandular: leaflets usually broader and 

 heads large : teeth entire. — T. oJduslflorum, Hook. Central Cahfornia. 



Var. MELANAXTHUM. Sniootli, often low : flowers smaller, dark-purple : 

 teeth entire or toothed. — T. inelananthum, Hook. & Arn. T. vark<jatuin, ^., 

 Torr. & Gray. S. California to Arizona. 



^ 31. T. PAUCiFLOKUM, Nutt. Smooth, very slender : involucre small: flowers 

 little exceeding the calyx, rather few : teeth rigid, setosely acuminate, entire. — 



