558 BORAGINACEAE 



in terminal spikes or racemes. Pedicels thickened at the summit and persistent. Calyx 

 5-divided, persistent, the segments narrow. Corolla salverform, white, yellow in the 

 throat. Stamens included. Ovary 4-divided; style short. Nutlets crustaceous, smooth or 

 variously roughened, attached at their bases or below the middle to the receptacle; scar 

 of the attachment concave or raised. [Name Greek, meaning diverse and nut, referring 

 to the great diversity of the surface of the nutlets.] 



A western North American genus of about 40 species, all but one annuals. Type species, Myosotis Chorisiana 

 Cham. 



Plants perennial, coarse, densely soft-villous with spreading hairs. \. A. mollis. 



Plants slender, annuals. 



Stems floriferous to near the base, prostrate; lower pedicels stout and recurved; calyx with indurated midrib, 

 its lobes irregularly spreading or recurved in age. 



Nutlets broadly ovoid, shiny, sparsely if at all tuberculate; scar surrounded by a high collar, about 

 one-fourth length of nutlet. 2. A. scripta. 



Nutlets lanceolate-ovoid, dull, granulate and tuberculate, scar not surrounded by a high collar, about 

 one-fifth length of nutlet. 3. A. humistrata. 



Stems not floriferous to base or if so the pedicels not stout and recurved. 



Scar longer, deeply excavated, lateral one-fourth to half the length of the nutlet; nutlets often with 

 prickles. 



Spikes mostly geminate; plant erect, glabrous or nearly so and somewhat succulent; corolla 4-6 

 mm. broad. 4. A. stricta. 



Spikes solitary at the ends of the branches, not geminate. 



Nutlets broad, about two-thirds to nearly as broad as long; usually armed with prickles. 



Nutlets not transversely rugose on the dorsal side, 2.5-3 mm. long; keel with prickles. 



5. A. Greenei. 



Nutlets transversely rugose on the dorsal side, 1.5-2 mm. long; keel and transverse 

 ridges with prickles. 



Prickles short and stout, covered with minute subulate trichomes. 



6. A. hystricula. 

 Prickles long and slender, glochidiate at apex. 7. A. acanthocarpa. 



Nutlets slender, about one-half as broad as long. 



Dorsal keel thin and knife-like, armed with prickles; dorsal surface between keels smooth 



or tuberculate, glossy. 8. A. Austiniae. 



Dorsal keel broader, not knife-like; dorsal surface between keels transversely rugose, dull 

 not glossy. 9. A. glyptocarpa. 



Scar smaller, one-fifth as long as nutlet or shorter, slightly if at all excavated, but margins sometimes 

 upturned, thus becoming somewhat concave. 

 Nutlet-attachment exactly or practically basal, often substipitate; calyx-lobes strongly costate; 

 plants somewhat succulent. 

 Stems prostrate; calyx-lobes connivent and turned to one side of flower. 



10. /i. leptoclada. 

 Stems erect or ascending; calyx-lobes spreading, not connivent to one side. 



Plant with fistulous-enlarged stems; lateral keel of nutlets well-developed; calyx-ribs promi- 

 nently indurated. 11. A. glabra. 



Plant with slender not fistulous stems; lateral keels less prominent; calyx-ribs only slightly 

 indurate. 12. A. stipitata. 



Nutlet-attachment lateral to obliquely basal ; calyx-ribs rarely enlarged. 



Scar linear or nearly so and borne on the edge of a knife-like keel or rarely cuneate and sessile 

 in undulata; coastal plants. 



Ventral keel in an elongate depression, only near the base becoming groove-like. 



13. A. undulata. 

 Ventral keel in a deep longitudinal groove the whole length, the groove sometimes infolding 



and more or less concealing the keel. 



Nutlets dull and granulate or tuberculate; stems prostrate or trailing. 



14. A. Chorisiana. 

 Nutlets smooth and shining; stems erect. IS. A. lithocarya. 



Scar broad, not linear. 



Racemes prevailingly geminate and bractless; erect dichotomous plants of the northwest 

 coast; corolla 4-9 mm. broad. 



Pubescence fine and soft, mostly appressed. 16. A. figurata. 



Pubescence spreading and more or less hispid. 17. A. hirta. 



Racemes solitary and bracteate at least at base. 



Stems with distinctly spreading hairs. 



Nutlets less than 2 ram. long, transverse ridges on dorsal side prominent; scar 

 lateral in a groove formed by ridges; racemes with 1 or 2 bracts near base. 



18. A. Cooperi. 

 Nutlets 2-2.5 mm. long, with low transverse ridges on dorsal side; scar supra- 

 basal, oblique, not sunken in a groove; racemes well-bracted. 



19. A. salsa. 

 Stems strigose or appressed-hispidulous. 



Scar of nutlet in an areole broader than long or areole wanting; nutlets often 

 asymmetrical. 



Corolla 2-5 mm. broad; plants mostly erect; calyx-lobes distinctly ferru- 

 ginous. 



Racemes rather dense, bracteate only at base, often geminate. 



20. A. granulata. 

 Racemes loose, bracteate to the middle or above, simple. 



21. A. Scouleri. 



Corolla 1-2 mm. broad; plants mostly spreading; calyx-lobes little if at all 

 ferruginous. 



Scar ovate to triangular, with thick margins divergent; nutlets dull. 



22. A. cognata. 



