ENGELMANN REVISION OF THE GENUS PINUS, ETC. 189 



botanical gardens and the curators or possessors of the great her- 

 baria, who most liberally furnished me with the material to carry- 

 on my investigations of the Pines and of the Conifers in general. 

 I am particularly indebted to Messrs. Bolander, Brewer, Parry 

 and Lemmon for their contributions of the Californian and Rocky 

 Mountain Conifers, and to Messrs. Canby, Oilman, Ravenel and 

 Mellichamp for those of the northern and eastern American 

 Pines. 



EXPLANATION OF FIGURES. 



PI, I. fig. I. A branch, gathered in September, showing; two mature cones, of the pre- 

 ceding years, flowering, and three young ones of the spring. One-half 

 nat. size, 

 fig. 2. Leaves in twos and threes. Nat. size, 

 tig. 3. Tlieir close serratures. Magn. 60 times. 



tigs. 4-7. Sections of leaves magnified 30 times, 4 and S of binate,6 and 7 of ternate 

 leaves; the ducts are seen closely appressed to the sheath which encloses 

 the vascular bundles; these bundles are, as in most pines, double, and 

 either separate or closely approximate and almost united ; the ducts are 

 wide or small, few or many, in these specimens, varying from 4 to 9. 

 PI. II. fig. S. Male inflorescence, capitate, with the elongated flowers in the axils of 

 fringed bracts. 

 One of the flowers, magn. 3 times, exhibiting the calycoid involucrum. 

 A bract, and 



The involucrum from the dorsal, and fig. 12 from the ventral side, exhibit- 

 ing the lowest lateral pair of bracts and the succeeding inner and upper 

 ones. Magn. 4 times. 

 PI. I. fig. 13. Diagram of the involucrum with the supporting bract; the 2 outer scales 

 are strongly, the 4 next ones slightly, keeled, 

 fig. 14 and ID bis. Effete anther from above and the side, showing the transverse 

 erect crest and one of the longitudinally opened cells. Magn. 10 times . 

 PI. II. fig. 15. Female aments in bloom, the axis above them already elongating, 

 fig. 16. The same, a little more advanced, 

 fig. 17. An anient magnified twice. 



fig. 18. A female flower (carpel scale) in the axil of the broad refuse bract —only 

 the upper, cuspidate, half being visible, and below the bifid tips of the 

 (rather clumsily executed) ovules — in February. Magn. lo times. 

 fig. 29. Female aments, six weeks or two months later, recurved. 

 PI. I. fig. 20. One of these, magnified. 



PI. III. figs. 21-24. Closed cones of difl'erent sizes and shapes, showing their variability, 

 fig. 25. Base of an open cone with spreading scales. 



figs. 26, 27, 2S. Scales of a cone. Fig. 26, dorsal view, showing the bract and the 

 apophysis; fig 27, view from above, exhibiting the impression made by 

 the seed and the surlace from which the wing had become detached; fig. 

 2S, section of a scale with the seed (exhibiting the embryo) and wing, 

 fig, 29. Seeds from the lower, and fig. 30 from the upper side, with difl!"erently 

 shaped wings ; in fig. 29, the rough under surface of the seed is seen ; fig. 

 30 shows its upper surface partly denuded of the wing-covering, 

 figs. 31 and 32. Albumen and embryo of different shapes. Magn. 4 times. 



