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VIII. Descriptions of two eee of the Natural Family of Plants called 
E. 
Coniferæ. By Davw Don, Esq., Libr. L.S., Prof. Bot. King's College. 
Read April 17th, 1838. 
THE Conifere undoubtedly constitute one of the most interesting families 
in the vegetable kingdom, whether considered in connexion with the former 
vegetation of the earth, or in reference to their peculiarities of structure, or as 
objects of utility, affording to man an abundant supply of valuable materials 
employed extensively in the arts and domestic eeconomy. Their habit and struc- 
ture are so peculiar that they have been ranked as a separate family by the 
earliest writers on Systematic Botany. Richard in his valuable work, “ Mé- 
moires sur les Coniféres et les Cycadées," has distributed the family into three 
groups, denominated by him, from the typical genera of each, Abietineæ, Cu- 
pressineæ, and Tarineæ ; the first may be characterized by their female spikes 
forming a cone or strobilus, their ovula being in pairs, and by their scaly buds ; 
the second by their reproductive organs having a tendency to become inde- 
finite, by their naked buds, and other peculiarities of habit; the third by their 
female spike being usually reduced to a single flower, with a solitary, com- 
pletely naked ovulum, whose external integument assumes a fleshy consist- 
ence and resembles an arillus. All three will be found to correspond remark- 
ably in the structure of their male flowers ; and the differences presented by 
their female inflorescence are more apparent than real, for they consist rather 
in the degree of reduction of parts than in actual structure. Their organs of 
nutrition present a remarkable degree of uniformity in their structure, and, 
indeed, it would be difficult to point out a family so completely natural, and 
one whose groups pass so insensibly into each other. 
To the three groups above mentioned I propose to add a fourth, which may be 
named Araucarinee, and to consist of Araucaria, Dammara, and perhaps Cun- 
ninghamia, which correspond with Cupressinec in the tendency of their repro- 
ductive organs to become indefinite, in their naked buds, and in their general 
habit. This group being mutually related to Abietinee and Cupressineæ, would 
