98 URTICACEAE. 



with light colored and rather smooth bark, trunk often 6-10 dm. 

 thick, branches spreading to form a well rounded scarcely depressed 

 head; leaves short-petioled, oblong, 5-8 cm. long, entire or sometimes 

 with a few coarse teeth, obtuse or retuse at the apex, rounded or 

 slightly cordate at the base, those of young shoots sometimes acutish 

 at both ends and coarsely serrate-toothed throughout, somewhat 

 coriaceous, almost without reticulation, downy-pubescent when 

 young, becoming glabrous in age; acorns sessile or peduncled; cup 

 hemispheric, tuberculate; nut oblong, about 2 cm. long. 



Frequent from Altedena and Alhambra to Monrovia; also oc- 

 curring at Azusa and Glendora, as well as in the foothills of San 

 Diego County. 



8. Q. dumosa Nutt. Shrub 1.5-5 m. high, the slender branches 

 tomentose when young; leaves coriaceous, sometimes persistent, 

 2 cm. long or more, oblong, obtuse, sinuate or sinuate-toothed, 

 dark green above, pubescent beneath; acorns sessile; nut oval, 

 2-3 cm. long; cup deep-hemispheric, 1-2 cm, broad, usually strongly 

 tuberculate, occasionally with somewhat flattened scales. 



Common in the chaparral belt of all the mountains. What 

 seem to be hybrids between this and Q. engelmanni are not infrequent 

 wherever the range of these two approach each other. 



Two species of oak grow on Santa Catalina that are not found 

 on the mainland. Q. tomentella Engelm. is related to chrysolepis, 

 but may be distinguished by the larger leaves which have prominent 

 parallel lateral veins. Q. macdonaldii Greene has deciduous leaves 

 that are deeply lobed; it is a small tree with finely checked bark. 



Family 22. URTICACEAE. Nettle Family. 



Ours annual or perennial herbs, with mostly stipulate 

 simple leaves and often with stinging hairs. Flowers in 

 racemed or panicled cymes (ament-like), with small 

 persistent bracts, monoecious or polygamous, small, 

 greenish. Petals none. Calyx mostly 4-parted or 

 sepals distinct, with as many stamens opposite the 

 lobes; filaments inflexed and anthers reversed in the 

 bud, straightening elastically at anthesis. Ovary super- 

 ior, 1-celled, 1-ovuled; style and stigma 1. Fruit an 

 achene. Endosperm oily, not copious; embryo straight. 



Herbs with stinging hairs; leaves opposite. 



Sepals 4, distinct. 1. Urtica. 



Staminate calyx 4-parted; pistillate un- 

 equally 2-4-toothed. 2. Hesperocnide. 

 He«bs without stinging hairs; leaves alternate. 3. Parietaria. 



