248 AMENTALES. [Diclinous Exogens, 



Alliance XVIII. AMENTALES. — The Amental Alliance. 



Diagnosis. — Flowers diclinous, m catJcins, acfdamydeous or monochlamydeous ; carpels 

 superior ; embryo small, toith little or no albumen. 



About the near alliance of the mass of genera hei^e collected, no reasonable doubt can 

 be entertained; and, in fact, they are associated in almost all systems of classification. 

 Then' strictly unisexual flowers, amentaceous inflorescence, and incomplete calyx, 

 afford the most obvious marks of identification. To this, however, the Order of Oleasters 

 offers an exception ; those plants are almost vmiversally referred to the \'iciuity of Daph- 

 nads (Thymelacese), among Perigynous Exogens, because the Elaeagnus is taken as the 

 type of their structm'e. I confess, howevei', that the latter genus seems to be far from 

 offering a correct idea of this peculiar Order, which is much better represented by 

 Hippophae and Shepherdia. Indeed, it is open to question whether the genus Elaeagnus 

 itself would not fall more properly into the ranks of Daplmads. Upon that supposition, 

 no doubt could be entertained of Oleasters finding then- most natural station here. 



Independently of the relations borne by Beefwoods (Casuarinaceae) to the Joint-fii's 

 among Gymnogens, it is evident that other strong lateral aflinities present themselves. 

 These are more especially manifest between Liquidambars and the Planes of the Urtical 

 Alhance, and between Galeworts and the Crowberries of the Euphorbial Alhance. 



If we attempt to trace a passage from Order to Order in the Alliance itself, it will be 

 observed that the winged fruit of Beefwoods is of the same uatm-e as that of their suc- 

 cessors the Bii'chworts ; that the latter are imitated by the Liquidambars, which may 

 be almost regarded as polyspermous Alders. If we suppose the two carpels of Liqui- 

 dambars to lose then- partition, and the seeds to be covered with hairs, Willowworts 

 would be the result of the change. At this point the series is mterrupted, for there is 

 nothing at present kno^vn to connect either Galeworts or Oleasters with Willows ; these 

 Orders are rather to be regarded as a modification of Beefwoods and Bu'chworts, by the 

 substitution of a fleshy for a membranous pericarp. Theu' true relation will be best 

 expressed thus : 



Joint-firs. 



Beefwoods — Birchworts — Liquidambars — WiUowvvorts. 



Galeworts. 



Oleasters. 



Natural Orders of Amentals. 



Ovary l-celled. Ovule I or 2, ascending. Radicle superior . . . 77. Casuarinace^. 



Ovary '2-celled. Ovule I , pendulotis. Radicle superior 78. Bet u lace js. 



Ovary 2-celled. Ovules 00. Seeds loinged 79. Altingiace^. 



Ovary \-celled. Ovules 00, Seeds cottony 80. Salicace^. 



Ovary \-cellecl. Ovule \, erect. Radicle superior 81. Myricace^. 



Ovary \-celled. Ovule ], ascending. Radicle inferior 82. El.eagnacea;. 



