184 BORftAGINACEiE. Heliotropium. 



lobes obtuse (with one exception) and usually broad : inflorescence in most species 

 either distinctly or indistinctly scorpioid. — § Euheliotropium & Orthostachys, 

 Benth. & Hook. Gen. ii. 844. Heliotropium & Schkidenia (Endl.), Fresenius in 

 Fl. Bras. viii. 31, 33. 



* Flowers all or some of them accompanied by bracts or leaves; when spicate, the so-called spikes 

 not naked, nor conjugate or forking to form a cyme, nor strongly coiled : anthers generally with 

 tips connivent or cohering over the stigma. — "§ Orthostachys, E. Br.; A.DC.; Benth. &"Hook. 

 Preslea, Mart. Schhidenia, Endl. 



-I— Stigma-tip elongated (sometimes 2-cleft): anther-tips lightly or only at first cohering: corolla 

 with naked and open throat, white : leaves narrowly linear : nutlets globular, beakless, externally 

 hispid or pubescent. 



■H- Divisions of the calyx similar, more or less shorter than the tube of the corolla: nutlets with a 

 pair of pits on the inner face. 



H. Greggii, Torr. A span high, diffusely spreading from a slightly woody hase, strigose- 

 cinereous : slender branches leafy : leaves narrowly linear, flat, about an inch long and a 

 line wide : flowers short-pedicelled or almost sessile in an at first crowded and short scor- 

 pioid spike, with 'or often mainly without bracts : corolla with an ample and slightly 

 5-lobed limb: anthers long, acuminate, minutely bearded at tip: stigma-tip subulate- 

 conical, much thicker than the very short style, as well as much longer. — Bot. Mex. Bound. 

 137 ; Gray, Proc. Am. Acad. x. 49. — Sandy or gravelly soil, western borders of Texas, New 

 Mexico, and adjacent part of Mexico, first collected by Dr. Gregg. Flowers very fragrant : 

 corolla a third to nearly half an inch broad when expanded. 



H. angustifolium, Torr. A span to a foot high, erect and densely branched from a 

 woody base, strigose-canescent : branches rigid, very leafy : leaves very narrowly linear, 

 with revolute margins, almost filiform when dry (4 to 9 lines long) : spike few-flowered, at 

 length slender, nearly straight, bracteate at base or without bracts : flowers small, short- 

 peduncled : corolla salverform, with narrow canescent tube and 5-parted limb ; the lobes 

 ovate-lanceolate (.acute !) ; hardly a line long, or half the length of the tube : anthers with 

 mucronate glabrous tips : stigma-tip slender-subulate, longer and hardly broader than the 

 rather long style. — Bot. Mex. Bound. 137. — South-western borders of Texas, Wright. 

 (Adjacent Mex., Gregg.) 



++ ++ Divisions of the calyx very unequal, the larger about the length of the corolla : nutlets 

 without pits on the inner face : inflorescence not in the least scorpioid. 



H. tenellum, Torr. A span to a foot high, erect from an annual root, paniculately 

 branched, slender, strigose-canescent : leaves narrowly linear, with more or less revolute 

 margins (about an inch long and a line wide) : flowers scattered, terminal, becoming lateral 

 and axillary, on rather slender peduncles, many of them bractless : limb of the corolla 

 rather shorter than the narrow canescent tube; the lobes oblong or obovate, a line long: 

 anthers oblong and with nearly naked blunt tips scarcely at all cohering : stigma-tip nar- 

 rowly subulate, 3 or i times the length of the short style. — Torr. in Marcy Rep. t. 14, St, 

 Bot. Mex. Bound. 138. Lithospermum tenellum, Nutt. in Trans. Am. Phil. Soc. ser. 2, v. 189. 

 L. angustifolium, Torr. in Ann. Lye. ii. 225, not Michx. — Open dry ground, Kentucky to 

 Alabama, west to Kansas and throughout Texas. 



•i— -t— Stigma-tip conical or more slender: anthers cohering by minutely bearded tips: corolla 

 appendaged and throat sometimes almost closed by a pubescent projection or gibbosity at or below 

 the base of each fold of the sinuses : divisions of the calyx usually of unequal breadth : nutlets 

 in our species beakless. 



++ Diffuse or tufted, a span or less high: internal appendages of the corolla small roundish puber- 

 ulent gibbosities low in the throat. 



H. OOnf ertifolium, Torr. Suffruticulose, very much branched and tufted, silvery-white 

 with a dense silky-hirsute pubescence : leaves crowded throughout and imbricated along 

 the upper part of the branches, from narrowly oblong to linear, 2 or 3 lines long, equally 

 white both sides, the margins somewhat revolute : inflorescence not in the least scorpioid : 

 flowers sessile among the leaves, mainly glomerate with them at the end of the branches 

 and hardly surpassing them : corolla pale purple ; its silky-hairy tube hardly longer than 

 the calyx ; limb angulate-5-lobed, only 2 lines in diameter : style thrice the length of the 

 ovary : annular stigma much broader than the subulate-conical tip. — Herb. Torr. H. Urn- 

 latum & var. confertifolium, Torr. Bot. Mex. Bound. 138, not H. Umhatum, Benth. — South- 

 western borders of Texas, Berlandier, Wright, &c. (Adjacent Mex.) 



