LOCALIZED STAGES IN DEVELOPMENT. 149 



a seedling (see Fig. 74). X?. Fig. a, section of primary lea£ .sliowing the form and tlie spines on tlic two angle.s. Compare 

 witli Figs. 73-74. P. 114. 



Fig. 77. Another .sucker from tlie stnmp, very vigorous and showing only reversionary primary leaves. Compare 

 Figs. 73-70. X|. Figs. 72-77, We.st Chop, Martha's Vineyard, Ma.ss. T. 114. 



PiNUS STKOBHS. 



Fig. 78. Seedling showing cotyledons bound together distally by the seed coats. X2. P. 115. 



. Fig. 79. An older seedling showing cotyledons expanded and succeeding primary leaves. X2. Cotyledons bear spines 

 on the three angles Fig. a, as in adult leaves. Primary leaves bear spines on two edges, Fig. b, as in Pinus rigida, Fig. 73a. 

 P. 115. 



Fig. 80. Still older seedling showing cotyledons and succeeding primary leaves. X2. Figs. 78-80, Arnold arboretum. 

 P. 115. 



Fig. 81. Older seedling, showing nepionic leaves at the base and bundles of 5 leaves in the a.xils of the primary leaves 

 at the top. (Part of the bundles are omitteil for the sake of clearness. ) x j. P. 115. 



Fig. 81a. One of the leaf bundles and subtending primary leaf . Xl. Fig. 81b, section of bundle in the plane nf the 

 sheath showing the angular form of leaves at that area. Kig. 81c, fragment of leaf slnnving form and three I'ows of niinule 

 spines on angles, much enlarged. Shady Hill nurseries, Bedford, Mass. P. 110. 



Larix occidentalis. 



Fig. 82. Seedling showing cotyleilons and succeeding nepionic primary leaves. X5. Kindness of Mr. C. E. Faxon. 

 P. 110. 



Larix europaea. 



Fig. 83. Fragment of adult branch .showing leaves in bundles on old wood, and pi'imary leaves only on current season's 

 growth. Compare with Fig. 82. Cultivated. Xf. P. 116. 



Figs. 78-80 drawn by Mr. J. H. Emerton ; others by the author. 



PLATE 22. 



Thdya occidentalis. 



Fig. 84. Seedling showing cotyledons, c, and succeeding nepionic leaves. 1, 2, are in whorls of four leaves, succeeded 

 by whorls of two leaves throughout succeeding growth. Primary leaves extend to top of the stem. Leaves on lateral 

 branches are appre.ssed, di.stally pointed (enlarged X4 in Fig. 84b). Beedes, Adirondacks, N. Y. X2. P. 119. 



Fig. 84a. Plan of arrangement of cotyledons and Hrst whorl of nepionic leaves of Fig. 84. P. 119. 



Fig. 85. Branchlet of adult showing characteristic leaves which are more abbreviated ami appres.sed than in the young, 

 as shown in Fig. 84b. Beedes, Adirondacks, N. Y. X4. P. 120. 



Fig. 80. Seedling showing cotyledcins and succeeding nepionic leaves. First nepionic leaves 1, a whorl of two leaves. 

 Second whorl, 2, four leaves ; succeeded by whorls of three leaves (an aberrant character in this species) on the main stem. 

 On the branch the leaves are in wlnnls of twos, and are soon abbreviated, appressed, as in the branch of Fig. 84. Culti- 

 vated. Audover, Mass. X2. P. 120. 



Fig. 80a. Plan of cotyledons c, and first three whorls of nepionic leaves 1, 2, 3, of Fig. 80. P. 120. 



Thuya gioaxtea. 



Fig. 87. Seedling showing cotyledons and succeeding growth. First nepionic leaves 1, in a whorl of two leaves, second 

 whorl 2, and succeeding whorls composed of foiu- leaves until near top of main stem, where some leaves are in whorls of 

 twos. On branches, leaves are in whorls of twos ; proximally, the leaves are elongate primaries, but soon the leaves are 



