Magnolia. POLYCARPILE. 25 



is also remarked in both the fossil and the living leaves. The oblitera- 

 tion of the areolation prevents an accurate comparison. This leaf is about 

 twenty-three centimeters long, and six centimeters broad above the mid- 

 dle. The average size of those of M. acuminata is twenty-eight centi- 

 meters long, and nine to ten broad. 



Habitat. — Chalk Bluffs, Nevada County, California. Voy's Collection. 



Magnolia Californica, sp. nov. 

 PI VI. Figs. 5-7. 



Leaves broadly oval, with entire, slightly undulate borders, rounded upwards to a short 

 acumen, and more gradually narrowed downward* to a short petiole; secondary 

 veins open, parallel, camptodrome, anastomosing along and quite near the borders 

 in simple or double bows. 



The fragment (Fig. 5) has the lateral nerves somewhat more distant, 

 and apparently thicker ; but, considering the leaves of living species of 

 Magnolia, these same differences are remarked. The relation of this spe- 

 cies to M. cordata, Mich., common in the present flora of the Southern 

 States, is quite as marked as that of the former species to M. acuminata. 

 The base is equal and cuneate to the petiole, while in the living species 

 it is generally unequilateral, and more or less cordate. Leaves narrowed 

 to the petiole, however, are frequently found in M. cordata ; indeed, young 

 leaves are generally of this character, and thouirh the base of the fossil 

 leaves are equilateral the lamina is divided by the midrib in two unequal 

 sides, as in the living species. All the details of nervation, as far as they 

 can be seen and have been carefully represented (Fig. 5), are the same, 

 even the basilar veinlets, as in Fitr. 7. In the fossil floras of the Mio- 

 cene of Europe, M. Diana;, Ung. Sillog., p. 28, PI. XI. Figs. 1-4, is the 

 more analogous species, differing especially by narrower leaves and the 

 winged petiole. Fig. 6 of our plate represents the cone-like receptacle 

 of a Magnolia with seeds still attached to it, and some loose ones upon 

 the same fragment. It is referable, very probably at least, to one of 

 these two species, whose specimens are all from the same locality. 



Habitat. — Chalk Bluffs, with the former. Voy's Collection. 



