5o6 The Ohio Naturalist. [Vol. XII, No. 6, 



KEY TO THE FRUITS OF THE GENERA OF TREES OF THE 

 NORTHERN UNITED STATES. 



John H. Schafkner. 



The complete fruit at maturity, including the peduncle, is recjuired 

 for determination. 



1, Fruit a cone, a cone-like catkin, a compact aggregate, or an 

 ordinary catkin. 2. 



1. Fruit simple, consisting of a single carpel or set of united 



carpels, not cone-like or catkin-like, but often clustered. 22. 



2. Fruit drv at maturity. 3. 



2. Fruit fleshy. 16. 



3. Fruit a globular aggregate of flowers on a long slender 



peduncle. 4. 



3. Fruit not globular, except in some true cones, but ovoid or 



cylindrical, peduncle short or if rather long then thick 

 and rigid. 5. 



4. Fruit an aggregate of dehiscent spiny-pointed capsules with 



several seeds Liquidambar. 



4. Fruit an aggregate of 1-seeded nutlets, not spiny-pointed. 



Platanus. 



5. Fruit a true cone with naked seeds, or an aggregate of closed 



carpels showing stamen, petal and sepal scars on the 

 peduncle. 6. 



5. Fruit a catkin or a cone-like catkin. 19. 



6. Seeds in closed carpels, the cone-like fruit showing stamen, 



petal, and sepal scars at the base on the peduncle. 7. 



6. Fruit a tnie cone wnth naked seeds, not showing stamen, 



petal, and sepal scars on the peduncle. S. 



7. Carpels of the fruit forming dehiscent follicles at maturity; 



the fleshy seeds suspended from the ]^ink or rose tissues of 

 the fruit by slender threads. Magnolia. 



7. Carpels samara-like, dry and indehiscent. Liriodendron. 



8. Cones with numerous ovuliferous scales, more than 15. 9. 

 S. Cones with 3-12 ovuliferous scales. 12. 



9. Cones erect, their scales deciduous from the persistent axis;. 



ovuliferous scales orbicular or broad, obtuse. Abies. 

 9. Cones pendulous or projecting from the branch, the scales 

 persistent. 10. 

 10. Cone scales woody and thickened at the outer end, elongated, 

 often with a rigid point, spine, or prickle. Pinus. 



10. Cone scales sub-orbicular or oval, sometimes with erose or- 



emarginate tips. 11. 



11. Cone with subulate leaf -scales at the base. Larix. 



11. Cone without subulate leaf -scales at the base, short and 

 ovoid, usually less than 13^2 in. long. Tsuga. 



