McKenney, Notes on Plant Distribution in Southern California. 171 



first set of herbs, a greener aspect is assumed. The forms of this 

 first series which are entirely or nearly restricted to the foothills 

 are: Nemophila insignis Doug., N. Menziesii H. et A., Plagiohoihrys 

 noihofulvus Gray, Gilia Siantlioides Endl., Calochortus albus Dougl. 

 aüd Mirahilü multiflora Gray. Brodiaea capitata Benth., Echino- 

 cystis fabacea Naud. and Eschscholzia californica Cham., which are 

 also abundant here at this tiine are found in several formations. 



In March the members of the second series attain their füll 

 development. These are : Layia platyglossa Gray, Madia sativa 

 Molina, Amsinckia spectabilis F. et M., Phacelia distans Benth., 

 P. tanacetifolia Benth., Salvia carduacea Benth , S. columbariae 

 Benth., Plantago pntagonica Jacq. var. nuda Gray and Hosackia 

 glaber Greene. During this period the hüls are a blaze of orange 

 owing to the great growth of Ctiscuta subinclusa D. et H. Alraost 

 all ot the scrub and often much herbaceous growth is attacked. 



During April and early May the third set of herbs reaches 

 maturity. The characteristic forms are: Allium serratum Wats., 

 Cotyledon lanceolata B. et H., C. pulverulenta Baker, C. caespitosa 

 Haw., Sedum obttisatum Gray, Chorizantke staticoides Benth., Cnicna 

 occidentalis Gray and Krinitzia leiocarpa Wats. In late May and 

 June we find Phacelia hispida Gray, /Solanum Xanti Gray, Calo- 

 chortus Catalinae Wats. and on the lower parts Nicotiana 

 Biglovii Wats. 



By the middle of July the majority of herbaceous forms have 

 fruited and, and least in their aerial parts, have withered. 



Ferns are found more frequently in the foothill formation than 

 elsewhere. They do not however constitute a prominent feature 

 of the formation. They frequently have a xerophile structure. This 

 is particularly true of Gymnogramme triangularis Kaulf. and Pellaea 

 andromedaefoUa Nee. The last, hard to point of brittleness, is the 

 only form in which leaves persist throughout the Dry season. 



Canon Formation: The most prominent feature of this 

 formation is the presence of trees. With the exception of the few 

 mentioned in the mountains, trees are restricted to this formation. 

 Trees are not found in all parts of the canons; but in the parts 

 where they do grow, they form groves. It is unusual to find 

 isolated specimens. This social habit does not produce tall straight 

 trunks. Usually the trunks are massive and the unbranched stock 

 is comparatively short. The crown is always large and spreading. 



These cafion groves are formed almost entirely by two species, 

 uamely Platanus racemosus Nutt, and Quercus agrifolia Nee. It is 

 as common to find groves consisting of either Quercus or Platanus 

 (Fig. 3) as it is to find both together. In the upper and narrower 

 parts of the cafions, Acer macrophyllus Pursh and Pseudotsuga 

 Douglasii Carr. var. macrocarpa Engelm. are frequent. Quercus 

 chrysolepis Liebm., a member of the mountain scrub frequently 

 wanders into the cafions and becomes arborescent. 



It is noteworthy that Platanus and Quercus are very unlike 

 in structure. The former has commonly two or three trunks 

 springing separately from the root System while the later has but 



