276 



MB HIERN, ON EBENACE^I. 



1. D. anceps. 



2. 

 3. 



D. vetwta. 

 D. Loveni. 



III. KEY TO THE FOSSIL SPECIES OF DIOSPTROS. 

 The species whose leaves have been described may be arranged as follows. 



Leaves more or less narrowed at base, or if sometimes rounded at base then acuminate at apex. 

 Leaves acute or subacute at apex (sometimes obtuse in D. brachysepala). 

 Petioles short, not exceeding in. in length. 



Leaves reticulated, secondary veins manifest, branched. 

 Leaves membranous, often unequal at the base. 

 Leaves coriaceous, equal at the base. 

 Leaves 2^ 3 in. long, ovate. 

 Leaves about 6 in. long, oval-oblong. 

 Secondary veins simple or subsimple, manifest. 

 Leaves about 6 in. long. 

 Leaves about 7 in. long. 

 Secondary veins obsolete. 

 Petioles long. 



Lateral veins rather distant. 

 Tertiary veins transverse. 

 Tertiary oblique or in various directions. 

 Midrib very stout ; net-veins subobsolete. 

 Midrib moderate ; leaves reticulated. 



Calyx 4-fid, with widely ovate or rounded lobes. 9. D. Irachysepala. 



4. D. Wodani. 



5. D. Lignitum, 



6. D. Weberii. 



7. D. alaskana. 



8. D. incerta. 



10. D. paradisiaca. 



11. D. lotoides. 



12. D. primceva. 



13. D. Auricula. 



14. D. dubia. 



15. 

 16. 



Calyx 5-partite, with linear lobes. 

 Lateral veins crowded, 



Leaves obtuse or .subobtuse; (sometimes acute .in D. varians). 

 Leaves lanceolate or ovate. 

 Secondary veins serpentine. 

 Secondary veins not serpentine, subremote. 

 Leaves about 3J 4| in. long, membranous. 

 Leaves about 2" in. long, subcoriaceous. 

 Secondary veins numerous, not serpentine. 

 Leaves J 1 in. wide. 



Tertiary veins reticulated. 

 Tertiary veins less lamified. 

 Leaves If in. wide. 

 Leaves oval or elliptical. 

 Leaves 2| 3| in. long. 

 Leaves -j% -^ in. wide. 

 Leaves 1^ in. wide. 

 Leaves 1| in. long by f in. wide 



Leaves rounded, not cordate at base, subobtuse, not rounded at apex. 

 Calyx 4-partite with oblong lobes; leaves oval, subcoriaceous. 

 Calyx deeply 4-fid, with widely elliptical lobes ; leaves oval-oblong, 



coriaceous ( . 22. D. Ulinica. 



Leaves rounded at both ends, .not cordate 23. D. oblongifolia. 



Leaves cordate at base. 24. D. Parthenon. 



D. varians. 

 D. obscura. 



17. D. palceogcea. 



18. D. hceringiana. 



19. D. pannonica. 



20. D. Royena. 



21. D. stenosepala. 



