OP ARTS AND SCIENCES. 335 



grayish tomentose underneath and somewhat silky-villous on the 

 prominent veins, entire, on petioles 3—5 lines long ; flowers in elongated, 

 interrupted, somewhat leafy panicles. It was found on the banks of the 

 Umpqua, Oregon, and is probably distinct. 



7. C. AZURi:us, Desf. Pubescent; leaves densely rusty-tomentose 

 beneath, smoothish above, 1-2^ inches long; thyrse more open. — 

 jMoun tains of Mexico from Tepic to Guatemala. 



H— -1— Low, the branches not rigidly divaricate nor spiny ; flowers in 

 short simple racemes or pedunculate clusters ; leaves small. 



a. Eastern species ; flowers white. 



8. C. MiCROPnTLLUS, Michx. Erect, nearly glabrous ; branches 

 numerous, slender, leafy, yellowish ; leaves thick, very small, 1-2 lines 

 long, fascicled, oblong-elliptic to obovate, entire or sparingly toothed, 

 on very short petioles; flowers in small terminal clusters. — Pine for- 

 ests of Georgia and Florida. 



9. C. SERPYLLiFOLius, Nutt. Decumbent, glabrate; branches 

 slender, brownish ; leaves less rigid and not fascicled, 3-G lines long, 

 oblong, serrulate, somewhat hairy beneath ; flowers in small clusters 

 on slender axillary peduncles. — Southern Georgia. 



b. Western species ; flowers blue. 



10. C. DENTATUS, Nutt. Erect, hirsutely pubescent, rarely nearly 

 glabrous ; leaves :^-l inch long, usually small and fascicled, obovate to 

 oblong-elliptic or lanceolate, acute at both ends or obtuse at the apex, 

 glandLdar-serrate, the margin becoming strongly undulate or revolute ; 

 flowers in small roundish clusters, on naked terminal peduncles about 

 an inch long; fruit resinously coated and somewhat triangular, the 

 valves being obscurely costate. — On dry hills in the Coast Range, from 

 Monterey to Mendocino; Douglas, Bigelow, and Brewer (n. 643, 984, 

 and 2374). The larger-leaved form (2392 Bolander) is C. Lohbianus, 

 Hook., and will also bo the G. diversifolius of Kellogg, if an}^ opinion 

 can be formed from his description. The smaller leaves are apparently 

 feather-veined, and often more or less resinous. 



11. C. DECUMBENS. Slender, trailing, hirsutely pubescent with 

 spreading hairs; leaves rather thin, flat, ^-1 J- inches long, elliptic- 

 oblong, somewhat cuueate at base, obtuse or acutish, glandular-serrate, 

 the greenish glands usually stipitate ; flowers in short dense shortly 

 pedunculate racemes, about \ inch long or less. — Frequent in the 

 mountains of Central California, from the Mariposa Grove northward ; 

 collected by Fremont (n. obi), Bigelow {^S. sorediatus of Whipple's 



