7(1 



NORTH AMERICAN FLORA 



[Volume 24 



XXIV. Pilosissimae 

 One species. 



XXV. PectinataE 

 Leaves glabrous. 



Leaves canescent. 



XXVI. Arenariae 

 Plant more or less pubescent. 



Calyx-tuhe villous; lobes lanceolate, more than half as long as the tube. 

 Calyx-tube glabrous or merely pubertilent when young; lobes triangu- 

 lar, scarcely half as long as the tube. 

 Plant densely short-villous; pod villous. 

 Plant sparingly !ong-villous; pod glabrous. 

 Plant glabrous. 



Bracts rather thick, not scarious-margined; calyx -lobes not ciliolate. 

 Bracts thin, with scarious lacerate margins; calyx-lobes ciliolate. 



105. P. pilosissima. 



106. P. pectinata. 



107. P. ahiclifolia. 



108. P. lanata. 



109. P. lerminalis. 



110. P. snbrillosa. 



111. P. glaberrima. 



112. P. scariosa. 



One species. 



XXVII. Mucronatae 



XXVIII. Eysenhardtioipes 



113. P. nnicronata. 



114. P. eysenhardtioides. 



115. P. leucostachys. 



116. P. Lumholtzii. 



Calyx-lobes deltoid-acuminate, fully half as long as the tube; spikes pan- 

 iculate, nodding. 

 Calyx-lobes triangular, acute, one third as long as the tube; spikes mostly 

 axillary, erect. 



XXIX. LUMHOLTZIANAE 

 One species. 



XXX. POGONATHERAE 



Spikes not very lax; corolla purple; plant with many stems. 



Calyx-lobes much shorter than the tube. 117. P. lasianthera. 



Calyx-lobes equaling or slightly exceeding the tube. 118. P. pogonalhera. 



Spikes very lax; corolla white; stem mostly single. 119. P. enneandra. 



XXXI. AUREAE 

 Leaves 3-foliolate. 



Leaflets linear or linear-oblanceolate, appressed silky-canescent. 



Leaves pinnately trifoliolate; corolla scarcely exceeding the calyx 



and the bracts. 120. P. hiisana. 



Leaves digitately trifoliolate; corolla about twice as long as the 



calyx and bracts. 121. P. Hallii. 



Leaflets obovate or oblanceolate. 

 Heads sessile or subsessile. 



Stems short, less than 2 dm. iong, ascending; leaflets broadly 



obovate. 122. P. Jamesii. 



Stems elongate, 2-4 dm. long, prostrate; leaflets oblanceolate. 123. P. trifoliolala. 

 Heads with peduncles 2-5 cm. long; stems erect, about 3 dm. high, 



few-leaved. 124. P. rubescens. 



Leaves 5-foliolate. 



Stems low, 1-2 dm. high, decumbent at the base; spikes sessile or 

 short-peduncled. 

 Leaflets sericeous on both sides, obscurely glandular-dotted. 



Bracts short-acuminate; spikes about 1 cm. thick. 125. P. nana. 



Bracts long-attenuate; spikes nearly 2 cm. thick. 126. P. Wrightii. 



Leaflets pea-green and sparingly hairy or glabrate above, sericeous 



but distinctly glandular-dotted beneath. 127. P. carnescens. 



Stems tall, 3-5 dm. high, with the upper leaves reduced and spikes 



rather long-peduncled. 128. P. aurea. 



XXXII. SERICEAB 

 Stem mostly erect, 5-10 dm. high, usually leafy more than half its height. 129. P. sericea. 

 Stem decumbent at the base, usually less than 3 dm. high, densely leafy 

 below. 

 Stems mostly herbaceous, simple; bracts not conspicuously scarious- 

 margined; corolla mostly blue. 130. P. gracilis. 

 Stems suffruticose and branched below; bracts conspicuously scarious- 

 margined; corolla rose-purple or the banner cream -colored. 131. P. reclinala. 



XXXIII. Versicolores 

 Plant not densely sericeous. 



Corolla (except sometimes the banner) dark-purple. 



Calyx-lobes shorter than the tube. 132. P. oaxacana. 



Calyx-lobes equaling or longer than the tube. 



Leaflets broadly oblong, 4-7 mm. long, glabrous above, not con- 

 spicuously involute. 

 Corolla rose-purple; calyx not conspicuously glandular be- 

 tween the ribs. 133. P. versicolor. 

 Corolla dark bluish-purple, almost black; calyx with a row 



of conspicuous glands between the ribs. 162. P. atrocyanea. 



