406 Prof. G. Gulliver on Raphides and other Crystals. 
XXXIX.— Observations on Raphides and other Crystals. 
By Grorce Guuiiver, F.R.S. 
[Continued from p. 295. ] 
Crassulacee, Ficoidee, and Cactacee.—In former examinations 
of a few of these plants, raphides were always found in Ficoidee, 
and never in Crassulacez and Cactacee. Of these three orders 
parts (leaves when not otherwise noted) of different species have 
since been obtained, chiefly through the kindness of Mr. J. 
De Carle Sowerby, Mr. W. H. Baxter, and Mr. Cox, of which 
the examinations will now be given. Crassula tetragona: a few 
oblong-cubic or prismatic crystals in liber or alburnum of stem, 
C. (perfossa?) : a few short, abruptly truncated prisms. Bryo- 
phyllum calycinum: some spheraphides and detached minute 
square crystals. Monanthes polyphylla (stem and leaf), Sedum 
populifolium (woody stem and leaf-buds), S. dentatum, S. 
kamskatkicum (root and leaf-buds), Sempervivum rubricaule, 8S, 
arachnoideum, S. anomalum, S. hirtum, Echeveria secunda, E. 
pumila, E. papillosa, E. bracteosa, Pachyphytum bracteosum, Co- 
tyledon? arborescens, C. umbilicus, Rochea falcata, and Tillea 
-muscosa: no raphides, and other crystals very scanty. Cereus 
hexagonus, C. flagelliformis, Rhipsalis paradoxa, protuberances 
and spines of seven species of Mammillaria, four species of 
Epiphyllum, and two of Opuntia were also all devoid of raphides. 
But in £. speciosum were numerous coarse spheraphides, a sort 
of crystalline grit, from which abruptly truncated prisms ra- 
diated ; and O. nigricans and fruit of O. vulgaris were thickly 
studded. with spheraphides, about ;4,th of an inch in diameter, 
especially in the outer part of the rmd; while in its imner part 
and parenchyma the sphzraphides were less numerous, more 
irregular in size, and so much larger that their mean diameter 
was not less than =+,th of an inch. Of the fifteen species re- 
ceived of Mesembryanthemum, every one abounded in raphides, 
commonly in bundles; and many larger crystal prisms were 
seen in these plants: the raphis-cells were generally of a short 
oval form, by no means so elongated as in many other orders, 
and in the centre frequently appeared black from the accu- 
mulation of raphides. This was well seen in the leaves of M. 
vaginatuin, M. densum, and M. caninum, and also in the paren- 
chyma and pith of the stems of M. barbatum, M. (tortuosum ?), 
and M. perfoliatum. 
In Prof. Balfour’s ‘Manual of Botany,’ these orders stand 
thus :—90, Crassulacer. 91, Ficoidee. 92, Cactacee. And now 
all the above observations show raphides constantly present m 
the section, Mesembryez of the central order, and as constantly 
absent in the two other orders. Still, that this remarkable 
Slept eerie eee. 
