CISTACE^E. 35 



the sepals and often the branches and peduncles canescently tomentose : 

 the primary or terminal flowers large, few or solitary, on peduncles about 

 as long as the flower ; secondary flowers axillary, very small, nearly sessile, 

 solitary or somewhat clustered on short leafy branches, the petals very 

 small or none, the outer sepals usually wanting. (Tb?T.) H. ramuliflorum 

 Mich. H. corymbosiim Pursh. H. rosmarinifolium Purth. Cistus Cana- 

 densis Linn. 



Sandy woods. Can. to Flor. W. to Miss. June Aug. 1\.. Stem about 

 a foot high, at length branching. Primary flowers an ioch in diameter, yellow ; 

 secondary ones often very numerous, with very minute capsules, in which stage 

 it has probably been mistaken for Lechea. I follow Torrey, Gray, and Darling- 

 ton, in uniting the several supposed distinct species above named. 



Rock Rose.. Frost Weed. 



2. H. corymbosnm Mich: stem branching from the base, canescent; 

 flowers in terminal fastigiate cymes ; the primary ones on filiform peduncles 

 much longer than the flower, the petals nearly twice the length of the 

 calyx ; the secondary flowers in glomerate cymules, mostly apetalous, 3 10 

 androus ; sepals tomentose villous ; the inner ones oblong-ovate, acute, the 

 outer linear and obtuse ; leaves oblong-lanceolate, softly canescent beneath. 

 (Torr. <$ Gr.) 



Sandy fields. N. J. to Flor. April May. '2].. Stem about a foot high. 

 Flowers about as large as those of H. Canadense. from which it is quite distinct. 



Corymbose Rock Rose. 



2. LECHEA. Linn. Pin Weed. 

 (In honor of John Leche, a Swedish botanist.) 



Calyx 3-sepalled, with two outer bracts or sepals, persistent. 

 Petals 3, inconspicuous, lanceolate. Stamens 3 12, and often 

 thrice the number. Ovary 1, 3-sided. Stigmas 3, scarcely dis- 

 tinct. Capsule 3-celled, 3-valved, with as many inner valves 

 opposite the others. Seeds affixed to the dissepiment or nerve, 

 very few, often 8. 



1. L. villosa Ell.: radical branches prostrate, villose; leaves oblong 

 lanceolate, mucronate, pilose ; panicle short, leafy ; flowers fasciculate-race- 

 mose, secund, on very short pedicels. L. major Mich. 



Dry woods. Can. to Flor. 'July. %. Stem I 2 feet high, erect. Leaves 

 on the radical branches opposite or verticillate ; those on the stem alternate. 

 Flowers small, brown, in racemose clusters:. Larger Pin Weed. 



2. L. minor Pursh. : nearly smooth ; stem assurgent ; leaves linear- 

 lanceolate and linear, acute ; panicle leafy ; branches elongated ; flowers on 

 short pedicels. 



Dry hills. Can. and N. S. July Sept. '7J.. Stem 812 inches high. 

 Flowers brown. Fruit larger than in the former. Smaller Pta Weed. 



3. L. racemulosa Mich. : whole plant covered with appressed pubescence ; 

 stem erect ; leaves linear, acute, ciliate ; panicle slender and very branching; 

 raceme naked ; flowers small, alternate, pedicellate. 



Sandy grounds. N. J. to Car. July. Tj.. Pursh. Perhaps only a variety 

 of the preceding Bunch-flovxred, Pin Weed. 



