26 DR. J. D. HOOKER ON THE STRUCTURE AND 
tion of Halorageæ, of which I regard them to be reduced forms, it cannot be disputed that 
amongst Phænogams there are few groups so uniformly incomplete as regards the normal … 
complement of organs, or the arrested development of those organs which are present, - 
The value of this consideration is however much diminished by the fact, that there are no | 
limits to the suppression of organs in the individual genera of Orders which are, never- - 
theless, typically highly developed. 3 
In a systematic point of view, the value of these suppressions in the Vegetable Kingdom — 
diminishes to a great extent in ascending from the root towards the ovary: thus, the - 
absence of a root of the ordinary structure, and the adaptation of the lower portion of the : 
stem to a parasitic attachment, occur in six or seven natural families of Exogens which — 
are normally terrestrial, and perhaps in many more. A total absence of leaves, or a — 
reduction of them to minute scales, occurs in many natural families. A reduction of the — 
whole plant to a leafless, single- or few-flowered stem, is found in many parasites, and in — 
Orchidee, Burmanniacee, Ericeæ, Scrophularine, Triuridee, Rafflesiace@, Gentianee, « 
and other families which have no mutual affinities; whilst the reduction of the inflo- | 
rescence to a single flower, and the parts of the latter to its essential organs, is too . 
frequent to need specification. That of the embryo to a homogeneous mass is found in — 
various genera, as indicated by Brown and Griffith: the reduction of the ovule to an 1 
embryo-sac is however, in the present state of our knowledge, almost peculiar to Bala- | 
nophoreæ. (3 
As regards the including the Monostyli and Distyli under one Natural Order, these 1 
are so manifestly different, that it is a theoretical question how far, were there more | 
genera of each, or had they a widely different geographical distribution, they would E 
by common consent have been united into one natural family: and the same argument 1 
might indeed be applied with equal force to the removing Mystropetalon and even Cy- 
It is difficult to indicate any particular genus of Balanophoreæ which can be considered 
typical of the Order, though Cynomoriwm may be taken as such for the Monostyli, and 
Helosis for the Distyli. Mystropetalon, though in many respects the most perfect 
genus of the Order, cannot in any degree be considered typieal of it; for it departs far 
more widely from the prevalent structure of its allies than any other genus does. Our 
es of aet IS or 1s not typical, are, however, vague and arbitrary; the ideal type 
ae = prevalent form of the group, or that which unites most of the pecu- - 
stinguish it, or that which possesses the fullest. complement of organs 
united in one individual, or that in which these are most compl ially 
* ex, as well as specially 
adapted to the functions they perform. : E 
N Classification of BALANOPHORE.E. 
In the following arrangement of Balanophoreæ, I have been chiefly guided by the 
structure of the female flowers which are sen: 
3 ’ erally f. . t 
characters for systematic en g y ound to afford the most important 
The primary division into Monostyli and Distyli was proposed by Griffith (Linn. Soc. | 
