FLOWERING PLANTS AND FERNS OF ARIZONA 337 



peduncles, large; petals 4 or 6, white or pale yellow; capsule oblong., 

 ovoid, or obovoid, 3- to 6-valved, dehiscent apically. 



1. Arctomecon humilis Coville, Biol. Soc. Wash. Proc. 7: 67. 1892. 



North of Wolf Hole, Mohave County, 2,700 feet, May {Peebles 

 and Parker 14749). Southwestern Utah and northwestern Arizona. 



A handsome plant, the flowers numerous, the petals 4, pure white, 

 the herbage sparsely hispid-hirsute. A. californica Torr. and Frem., 

 a larger, much hairier plant, with usually 6 yellow petals, has been 

 collected near Pierce Ferry, northern Mohave County (Hester in 1941). 



5. CORYDALIS 



Plant herbaceous, biennial or short-lived perennial; herbage glab- 

 rous, glaucous; leaves dissected into numerous small segments; flowers 

 very irregular, in spikelike racemes ; sepals 2 ; corolla yellow ; capsules 

 elongate, cylindric, usually curved, 2-valved, more or less torulose; 

 seeds numerous, black, shining. 



The plants contain several alkaloids and are said to be poisonous to 

 sheep, less so to cattle, if eaten freely. 



1. Corydalis aurea Willd., Enum. PL 740. 1809. 



Capnoides aureum Kuntze, Rev. Gen. PL 1: 14. 1891. 



Throughout the State except the extreme western portion, 2,500 to 

 8,000 feet, February to June (sometimes also in late summer). Nova 

 Scotia to Alaska, south to Pennsylvania, Arizona, northern Mexico, 

 and California. 



Many of the Arizona specimens may be regarded as belonging to 

 var. occidentalis Engelm. (Corydalis montana. Engelm.) which is 

 described, in comparison with typical C. aurea, as having the spur 

 longer relative to the rest of the corolla, the pods less torulose and 

 ascending-incurved rather than spreading or pendulous, the stems 

 more erect, and the racemes denser, with more numerous flowers; 

 but there is no close correlation among these characters and plants 

 intermediate in respect to one or all of them are numerous. 



Corydalis wether illii Eastw., based on a collection near Bright Angel Creek, 

 Grand Canyon (A. Wetherill in 1897), is described as having more finely dissected 

 foliage, and pinkish outer petals. 



C. jonesii Fedde, C. jonesii var. stenophylla Fedde, and C. pseudomicrantha var. 

 griffithsii Fedde are based on types collected in Arizona, but none of them seem 

 to be satisfactorily distinguishable from C. aurea and its var. occidentalis. A 

 specimen collected on the San Francisco Peaks (Purpus 7058) was identified by 

 Fedde as C. gooddingii Fedde. Specimens from Pima County with exceptionally 

 large bracts and with pinnae at base of the petioles (Griffiths 3553, Eggleston 19825, 

 Tourney in 1896) are C. campestris (Britton ) Fedde (C. curvisiliquaeformis Fedde, 

 Capnoides euchlamydeum Woot. and Standi.), but it is doubtful that this form is 

 more than varietally distinct from C. aurea. 



46. CRUCIFERAE. Mustard family 



Plants herbaceous or (in Lepidium) sometimes suffrutescent, annual 

 or perennial; leaves alternate, commonly simple and entire to pinnati- 

 fid (pinnate or bipinnate in Descurainia); flowers perfect, regular; 

 sepals and petals 4, the petals rarely wanting; stamens usually 

 6 and usually tetradynamous (1 pair shorter); fruit a capsule (silique 

 or silicic), commonly 2-celled, with a thin longitudinal partition and 

 dehiscent, or 1 -celled and indehiscent in a feu eeriera. 



