RAPHIDES. IN. ONAGRACEZE AND HYDROCHARIDACER, 69 
But. they often contained spheeraphides ; as was beautifully seen in 
Haloragis, and especially in thin slices of the stem and leaves of Zox- 
donia ; they should be compared with similar objects in Jzora and 
Gardenia, and in the rind of the fruit of Opuntia vulgaris. 
At present, I have no opportunity of referring to our highest autho- 
rity, (Lindley’s ‘ Vegetable Kingdom °) on the alliances of Onagracea. 
In Professor Balfour's valuable ‘Manual of Botany’ the Orders run . 
thus :—78, Philadelphiacee ; 19, Myrtacee ; 80, Onagracee ; 81, Ha- 
loragacee; 82, Loasacee. Now, still excepting Onagracee, al the 
above-named plants belong. to. these different Orders; and while Ona- 
gracee is an Order regularly abounding in raphides, every native and 
exotic plant, hitherto examined in relation to this question, of the next 
allied Orders, has been found destitute of raphides. ey 
_ And, conversely, as, far, as my observations yet extend, a single 
Order, of which Hydrocharidacee affords an example, may be character- 
ized as devoid of raphides, and yet standing between Orders abounding 
in raphides. For, while these acicular crystals were always found in 
Paris quadrifolia, Tamus communis, Dioscorea Batatas, Testudinaria ela- 
phantipes, roots of Sarza, and in such British and foreign Orchids as 
T have hitherto examined, raphides could not be discovered either in 
Fallisneria spiralis, Anacharis Aisinastrum, Stratiotes aloides, or Hy- 
drocharis Morsus-rane. 
l Several other examples to the same effect as those of Onagracee and 
Hydrocharidacee probably exist. But my observations are yet by no 
means’ sufficiently comprehensive to afford more than rational hypo- 
theses which-indicate the necessity for further research in this direction. 
Thus, such Orders as Balsaminacee, Ficoide, Alismacee, and Potamo- 
getonacea; especially invite more inquiry, since the results of the few 
examinations which I have made of these Orders and their allies, show 
raphis-bearing ;Balsams, immediately surrounded by Geraniums and 
Flaxes, Oxalids and Indian Cresses, in which (on the contrary) raphides 
are not! found ; raphis-bearing Ficoids, standing between House-lee 
and. Indian Figs without raphides; Water Plantain and Pondweeds 
destitute. of raphides, which nevertheless abound in all the Orders 
placed between these two genera in Professor Babington’s ‘ Manual of 
British Botany.’ 
But the whole subject is so vast as to be quite beyond the powers of 
ah out-door naturalist, mostly confined to the narrow sphere of a rural 
