QuERNALEs.] QUERNALES. 289 



Alliance XXI. QUERNALES. — The Quern al Alliance. 



Diagnosis. — Diclinous Exogens, with amentaceous monochlamydeous $ floivers, an infenor 

 fruit, and an amygdaloid embryo without allmmen. 



The Alliance, which comprehends the common Oak and the Beech tree of Europe, is one 

 whose limits are in no degree invaded. The truly diclmous epigjTious flowers, the ^ of 

 which are unifomily arranged in catkins, and the exalbumuious seeds wdth a large 

 amygdaloid embryo, offer marks of recognition not to be mistaken. That the Walnut 

 is nearly aUied to the Oak seems incontestable, although it is often placed in a very 

 different part of the system. Its diclinous epigjaious amentaceous flowers, and superior 

 radicle, are entu*ely those of the Mastworts, and the crumpled cotyledons of Quercus 

 Skinneri are an imitation of those of the Walnut itself. Indeed if the Walnut had 

 a many-celled fruit and a cupule, there would be no very good reason for separating 

 it from Mastworts, except its resinous juices. 



At this point the Diclinous Sub-class touches the PerigjTious, where the Terebints, 

 having in some instances diclmous flowers, as is the case with Pistacia, come up to 

 the very limits of Juglands. On the other hand, the M;yTobalans in the Myrtal 

 Alhance are not very different from hermaphrodite Mastworts, and establish a less 

 close, but well-marked, approach on the part of the EpigjTious Sub-class. 



The transition from the Quemal Alliance seems to be formed by Garrya itself, 

 whose flowers are so much Hke those of Juglans, although the habit is different, that if 

 it were not for the minute embryo and large mass of albumen in Garrya it might take 

 its place in the Quemal Alliance. 



Natural Orders of Quernals. 

 Ovary 2- or more celled. Ovules pendulous or peltate . . 95. Corylace^. 

 Ovary \-celled. Ovxde solitary, erect 9Q. JuGLANDACEiE, 



