12 
CONTRIBUTIONS TO BOTANY. 
escape of the pollen, but at the apex the spaces over the cells 
become depressed, and may be mistaken for two open pores, 
which are also covered by a network screen, as before described, 
in the anthers of Cathedra. I have met with several other cases 
of somewhat similar structure in many genera of the Santalacece, 
and in some instances also in Olacacea, where however a form of 
anther prevails, which, though somewhat analogous, must not be 
confounded with the structure above described. Here the an- 
thers are distinctly 4-lobed, 4-celled and 4-valved, often more or 
less crustaceous in texture, the cells opening alternately right 
and left by the evolution of the valves, which separate from the 
connective longitudinally by one of their margins, so that when 
these are rolled back the pollen is discharged, and they appear 
as if the anthers had been 2-celled and 4-valved, according to 
the usual mode of construction. The same development often 
occurs in Loranthacece proper, in Rhamnacea, Celastracece, and 
other families, although they are generally considered to have 
bilocular anthers ; in these instances the valves are much thinner 
and reticulated in texture ; they are the same in Psittacanthus ; 
but in Struthanthus, though the walls are crystalline, and as thick 
as in Cathedra, they yet open in the manner just described. 
The comparison of the characters of Cathedra with other ge- 
nera has led me into a general examination of the Olacacea, San- 
talacece, and other allied families, in the course of which I have 
met with numerous interesting and novel facts, and from the 
materials thus collected, I propose to give at an early period, a 
review of each genus belonging to these orders in succession, 
together with illustrated details of their characters. In the fol- 
lowing memoir on Liriosma, I will offer some of the views I have 
in consequence been led to adopt regarding the affinities of the 
families above alluded to. 
The singular development of the very remarkable free cupuli- 
form disk in Cathedra, that supports on its margin the petals 
and stamens, is an important feature, as it serves clearly to de- 
monstrate the true nature of the same organ, which, with few 
exceptions, in all ivne-Olacacece, is always more or less adnate 
with the o^■arium and quite free from the calyx, but which in 
the genus Liriosma is connate with the calyx and wholly free 
from the o\ arium ; while in those genera of the Santalacece, 
where the calyx and corolla are continent in one common peri- 
gonium, the disk is almost wholly coadnate with the latter : to 
this feature therefore, as it is developed in Cathedra, frequent 
recurrence will be made when we come to consider the different 
genera in the manner I have proposed. The ovarium in the 
plant under consideration is turbinate and flattened, the lower 
moiety being smooth and concealed within the free surrounding 
