APPENDIX 



Key to Genera and Species 



la. Ovary inferior, adnate to the hypanthium; fruit a pome. 



2a. Leaves sessile or nearly so, alternate but fascicled 

 at the ends of the branchlets; flowers solitary or 

 two to three together; styles two. . .Feraphyllum 

 ramosissimum 



2b. Leaves petioled, not fascicled at ends of branchlets; 

 flowers mostly several to many in a raceme; styles 



two to five AmeZanohiev 



3a. Leaves mostly glabrous at maturity; petals usually 

 more than 10 mm long; styles usually five; fruit 

 glabrous, 10-15 mm in diameter, normally with 10 



locules A. alnifolia 



3b. Leaves finely pubescent; petals usually less than 

 10 mm long; styles two to four (rarely five); fruit 

 frequently pubescent, 6-10 mm in diameter, with 



three to six locules A. utahensis 



lb. Ovary superior, not adnate to the hypanthium, fruit an achene. 

 4a. Flowers inconspicuous; petals lacking. . . Cerooaar'pus 

 5a. Leaves deciduous, flat; margins dentate . . . 



C. montanus 



5b. Leaves evergreen, somewhat revolute; margins entire 

 or dentate. 



6a. Leaves, at least some, with margins dentate; 



a hybrid . . . . C . montanus X C. ledifolius 

 6b. Leaves entire, usually strongly revolute. 



7a. Leaves elliptic, over 12 mm long; plants 



tall shrubs or small trees 



C. ledifolius 



7b. Leaves linear to narrowly oblong, usually 



less than 12 mm long; plants low, intricately 



branched shrubs C. intriaatus 



4b. Flowers showy; petals present. 



8a. Leaves pinately compound; achenes enclosed in the 



fleshy calyx tube Bosa woodsii 



8b. Leaves simple; achene(s) not enclosed in a fleshy 

 calyx tube. 



9a. Bractlets present at base of flower; pistils 



more than 12 Fallugia paradoxa 



9b. Bractlets absent; pistils less than 12. 



10a. Pistils four or more; styles becoming 

 elongated and plumose; leaves usually 



with five or more lobes 



. . . . Cowania mexieana var. stansburiana 

 10b. Pistils less than four; style not markedly 

 elongated or plumose; leaves usually with 

 five or less lobes. 



11a. Pistils two to three; style slightly 

 elongated or plumose; leaves usually 

 with three to five lobes; a hybrid . . 



Cowania mexioana var. stansburiana X 

 Purshia tridentata 



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