EXPLANATION OF THE PLATES. 



Plate DLXXI. Pestus Coulteri. 



1. A branch with staminate flowers, natural size. 



2. An involucre of a staminate flower, enlarged. 



3. Diagram of the involucre of the staminate flower. 



4. An anther, front view, enlarged. 



5. An anther, side view, enlarged. 



6. An end of 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. A cone, one year old, natural size. 



10. Tip of a leaf, enlarged. 



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



12. A seedling plant, natural size. 



13. A winter branch-bud, natural size. 



Plate DLXXIL Pinus Coulteri. 



1. A cone, natural size. 



2. Seeds, natural size. 



3. A seed-wing, natural size. 



4. Vertical section of a seed, enlarged. 



5. An embryo, enlarged. 



