EXPLANATION OF THE PLATES. 



Plate DLVIL Pestus Torreyana. 



1. A cluster of staminate flowers, natural size. 



2. An anther, front view, enlarged. 



3. An anther, side view, enlarged. 



4. Diagram of the involucre of the staminate flower. 



5. An involucre of a staminate flower, enlarged. 



6. A branch with pistillate flowers, natural size. 



7. A scale of a pistillate flower, lower side, with its bract, enlarged. 



8. A scale of a pistillate flower, upper side, with its ovules, enlarged. 



9. Cross section of a leaf, magnified fifteen diameters. 



10. Tip of a leaf, enlarged. 



11. A cluster of young leaves, with its sheath, natural size. 



Plate DLVIII. Pinus Torreyana. 



1. A fruiting branch, natural size. 



2. A cone-scale, side view, natural size. 



3. A seed with its wing, side view, natural size. 



4. A seed with its wing, natural size. 



5. A seed-wing, natural size. 



6. Vertical section of a seed, natural size. 



7. An embryo, enlarged. 



8. A seedling plant, natural size. 



