SEQUOIA SEMPERVIRENS. I 75 



EXPLANATION OF PLATES. 



The figures in plates xv and xvi are the natural size. Plates xvii and 



xviii are magnified. 



Plate XV. 



Fig. 1. Fruiting twig from a low branch of a small tree in Mill Valley, 

 Marin County. The tree had grown from one of the suckers of a tree that 

 had been felled many years ago. It shows the well-known broad distich- 

 ous foliage. 



Fig. 2. Flowering branch from the upper part of a small tree in the 



same locality. The young upper leaves are scale - like, but afterwards 



broaden out. 



Plate XVI. 



Fig. 1. Fruiting branch from the upper part of a medium sized tree 

 growing at the head of Sequoia Canon. This is the characteristic upper 

 foliage of the large trees — short, stout, scale-like leaves, similar to those of 

 S. gigantea. 



Fig. 2. Lower branch of the same tree with distichous foliage. 



Fig. 3. Small twig with proliferous cone. 

 Plate XVII. 



Fig. 1. Broad leaf from the twig shown in plate xv, fig. 1. The canal 

 down the center which is near the surface makes the central ridge seem 

 depressed. Figs. 5 and 10 are cross-sections of similar leaves. The po- 

 sition and number of the resin ducts are seen to be variable in the differ- 

 ent cross-sections of leaves oiS. sempervirens, figs. 5, 10, 6, 7, 8, 9. In these 

 sections tjie epidermis is represented by the parallel vertical dotted lines, 

 the cross-sections of the resin duct by the openings, and the wood cells by 

 the horizontal parallel lines. 



Fig. 2. Young appressed leaf of branch shown in plate xv, fig. 2. The 

 resin duct is nearer the surface at the vipper and lower part of the leaf. 

 The small irregularly placed dots represent the stomata. Fig. 6 cross- 

 section of similar leaf. 



Fig. 3. Leaf from the branch shown in plate xvi, fig. 2. Figs. 8 and 9 

 sections of same. 



Fig. 4. Leaf from branch shown in Plate xvi, fig. 1. Fig. 7 cross-sec- 

 tion of similar leaf. This is the form that resembles S. gigantea, as can 

 be seen by comparing cross-sections. Figs. 11 and 12 sections of leaves of 

 S. gigantea. Fig. 13 cross-section of the bract of a staminate ament. 



Figs. 14 and 15. Sections of pistillate scales of S. sempervirens. It is 

 not usual to find more than one resin duct in these scales. Figs. 16 and 

 17, sections of pistillate scales of S. gigantea. 



