CONTRIBUTIONS TO BOTANY. 
11 
upon this subject ; these have been clearly described by 
botanists as being formed of numerous, aggregated and di- 
stinct cells, each filled with pollen-grains, and which dis- 
charge these fertilizing particles by as many distinct pores, in 
a manner that has been described and clearly delineated by 
Richard in the ^Ann. Mus.^ xii. p. 296. tab. 27. fig. 3. M. 
DeCaisne, in a learned memoir on the development of the 
pollen in Viscum album (Mem. Acad. Bruxelles, vol. xiii.), details 
the mode of growth of its anthers, and exhibits highly magnified 
transverse sections of the same in their different stages, but does 
not give a single vertical section, nor any description or drawing 
of the anther in its mature state : we may therefore conclude that 
he coincided with the description of Richard, in regard to its 
being composed of an indefinite number of distinct aggregated 
pollen-cells ; he seems indeed to confirm this structure, for in 
his memoir just quoted, tab. 1. fig. 3, he shows a transverse sec- 
tion of an anther advancing to maturity, where nine such cells 
radiate upon its inner face, and in fig. 4 he gives a section of one 
of these distinct cells filled with pollen-grains. Endlicher repeats 
the same view of the structure of the anthers in Viscum, as being 
“ multicellulosse, poris plurimis dehiscentes.” Prof. Bindley con- 
firms the same statement (Veg. Kingd. p. 790), where he says, 
“ in the genus Viscum the anther forms its pollen in a number 
of distinct cells, as in JEgiceras, this being beautifully illustrated 
by DeCaisne (Mem. Acad. Brux. he. cit.). Not having any 
opportunity of examining the structure of the anthers in Viscum 
album, I will not attempt to deny the facts vouched for upon 
such authority, but I can speak with confidence to what I have 
unquestionably observed in regard to their structure in dried 
specimens in all the Brazilian species of Viscum that I have ex- 
amined. Here they are constantly free and sessile upon the 
base of the lobes of the perigonium, and on the margin of an 
adnate cupuliform disk ; they are bilocular, the cells being par- 
allel and of the whole length of the anther ; these cells are filled 
with numerous pollen-grains, and are formed of very thick cry- 
stalline walls, consisting of large cellules, radiating around each 
central pollen-cell, as in Cathedra ; and these cellules are closed 
at both ends by the external and internal facings of the walls, 
which are thin and marked with close-set parallel interrupted 
lines, as are also the lateral divisions between these cellules. 
On a future occasion I shall be able to show that other dif- 
ferences exist in the structure of the seed, in the tropical 
species of Viscum, which are not less striking than the fact 
here recorded respecting the conformation of the stamens. 
In my examination, I have not been able to perceive in any in- 
stance, an indication of the bursting of these two cells for the 
