renewed on older wood for 15 years. Shed en masse November, leaving circular 

 scars, renewed laterally. 



Staminate flowers panicled, on ramuli without needles, 3-5 in. branch systems, 

 at ends of laterals: 5 mm., with internodal extension above perianth; stamens (15) 

 spirally arranged ; pollen-sacs 3-6. 



Ovulate flower solitary, of short bract-scales, with 2 erect ovules per scale ; cone 

 an inch or more diam., very solid, ellipsoidal, matured in one season, of mucronate 

 bract-scale portions and crested cone-scale portions : seeds erect, 2 per scale ; cots. 6. 



Note. Special case of ' respiratory roots ' (knees) in swampy ground. 



T. mucronata, evergreen, Cypress of Montezuma, the big tree of Tule (Mexico), 

 over 50 ft. diam., trunk thickened by descending roots. 



IV. Sciadopitys verticillata, Umbrella Pine; Japanese monotype, 90-150 ft., 

 and 3 ft. diam., pyramidal ; with bifoliar spurs in double cycles as false whorls of 

 needles (in the manner of starved Pinus sylveslris), but needles large and fused as 

 ' double-needles ', 3-4 in. 



Staminate flowers clustered at end of shoots ; pollen-sacs 2 per stamen. 



Ovulate flowers usually solitary, giving cones 2-3 in. long, scales 2:3:5 seriate, 

 of distinct transverse regions : seeds inverted, about 7 per scale, with lateral wing- 

 margins ; cots. 2. 



Theory of Abietineae : Comparison of the few surviving types, beyond the case of the highly 

 specialized Pinus, shows that the original habit included needle-foliage on the main shoots (retained 

 as ' juvenile-leaves ' in Pinus) and the general production of laterals as leaders at any point on the 

 annual shoot {Cedrus, Larix, Picea, Abies, Pseudotsugd), a relic of which is regarded in Pinus as the 

 ' multinodal ' condition. Radial organization of the branch-system is clearly older than phases of 

 dorsiventrality, the latter being most advanced in species of Abies and Tsuga. Early stages of spur- 

 differentiation are seen in Cedrus and Larix to be further specialized in Pinus. Larix and 

 Pseudolarix attain to the deciduous habit. 



The flowers are simple strobili, terminating laterals, and exhibit a marked tendency to 

 minimum reduction : Cedrus retains the finest micro-strobili, and all show the minimum construction 

 of two pollen-sacs per stamen. Winged pollen is a novelty, and the older condition is retained in 

 Larix and Pseudotsuga. The number of ovules per carpel is also constant at the symmetrical 

 minimum of 2, and the cone-scale is dominant in cone-formation, the developing seeds being 

 protected by the overlap and mutual growth-pressures of these scales, which subsequently again 

 diverge to allow the dispersal of the seeds. Pinus alone attains the sealing mechanism of the 

 apophyses, though Cedrus is also a 2-season cone. It is clear that a one-season cone is the normal 

 case {Picea, Larix, Abies, Tsuga), and the peculiar precocity of the cone-scale in Pinus also obtains 

 in Picea, Tsuga, and Cedrus; though any special efficiency in pollination remains doubtful, since in 

 Larix, Pseudotsuga, and Abies the bract -scales are still effective as pollen-catching members. In the 

 latter again the bract -scale may remain prominent in the adult cone, thus enhancing its original 

 significance, as also possibly its original morphological differentiation {Pseudotsuga). The precocity 

 of this ' cone-scale ' formation is apparently connected with rapid sealing of the cone after pollination, 

 in its perennating stage during the growth of the sexual individuals. 



The small wind-dispersed seed with cone-scale slip for ' wing ' is constant for all as an efficient 

 mechanism, and the older condition of shedding cones, and even scales ( = carpels), in Cedrus, Abies, 

 Pseudolarix, of which vestigial traces may be traced in Pimis, is still dominant in these more 

 archaic types. The vertical orientation of cylindrical cones is also the simplest case, as involving 

 only one geotropic correction ( ve ), Abies, Cedrus ; inversion {Pinus, Picea) is secondary, and 

 requires a clear internodal extension in the cone-stalk, the lack of which results in eccentric 

 development in many Pine-cones. 



Theory of Taxodineae : Among the few surviving types of this series it will be noted that 

 specialized foliage-needles give place to more elementary reduced scale-leaves {Sequoia, Cryptomeria, 

 Arthrotaxis). Radial symmetry and indefinite production of laterals is the rule; winter-buds may 

 be wanting {Cryptomeria); dorsiventral foliage and shoot -systems {Sequoia sempervirens and 

 Taxodium) may be associated with advancing spur-organization, the first indications of which 

 are traced in Sequoia gigantea : yet Sciadopitys passes on to a stage with a monophyllous bifoliar 

 spur-formation in false whorls, even beyond the condition of the 2-needled Pines; showing that 

 a type which may remain elementary in one respect may be highly organized in some other. 



The flowers also present more generalized factors, though all are small and much reduced ; the 

 poUen-sacs are typically more than 2 per stamen (5-6), and the ovules similarly per carpel (10). 

 None attain to winged pollen, and the cone-scale region is never functional in the stage of pollination. 

 The simplest ovulate flower is presented by Cryptomeria, with erected ovules exposed in what is little 

 more than a spiral bud-ccnstruction. 



The cone-scale is only significant in the formation of the green-cone, as a crested outgrowth ot 

 the bract-scale, carried up by intercalary extension to seal the scales, otherwise rudimentary and 

 ineffective. There is no secondary inversion of the cones, but separation of the scales on desiccation 

 is normal ; nor are the scales shed individually. 



The seeds are small, but in all cases any ' wing '-extension is due to the testa, and there is no 

 wing-slip cut off the cone-scale. Cryptomeria appears as the most generalized and archaic type of the 

 series, because it presents the least number of factors of secondary specialization. 



22 



