Miscellaneous. 
407 
nearest to that of the large extinct Edentata, the Mylodons ; but the 
structure of the symphysial portion is unlike that of any other 
animal. Dr. Mantell will shortly present a memoir on this most 
interesting discovery to the Royal Society, in whose Transactions 
his first memoir on the Teeth of the Iguanodon was published in 
1825. The lower jaw, containing teeth, was discovered by Captain 
Bickenden, the upper by Dr. Mantell : both are from the same loca- 
lity in Tilgate Forest. 
Description of a new British Mould. By George Johnston, M.D. &c. 
I am willing to believe, with my Lord Bacon, that Mould “ is 
something between putrescence and a plant.” It settles a much- 
mooted point as well as any other theory has yet done. Organic 
substance, in a state of decay, is Mould’s fruitful matrix, — life from 
death, — the ever-yearning change from a worse to a better condition ; 
for life, even in this its lowest state, is better certainly than sad 
corruption. And how beautiful are many Moulds, when, with the 
microscope, we discover Nature’s handicraft in them to the eye of 
sense ! We can scarcely but believe that they have a sort of enjoy- 
ment in their life, and in the evolution of their symmetrical figures. 
One sort is now vigorous and abundant on some plants in my little 
“ Green-house,” where it is as noxious as the Green-fly, or Aphis ; 
and it is rather singular that the species has not been yet recorded 
as a British production. I have the high authority of the Rev. M. 
J. Berkeley for this fact, who informs me that our Mould is the Bo- 
trytis umbellata"^ of DeCandolle. 
Botrytis umhellata. On a flat and smooth leaf, the decumbent fila- 
ments of this Mould form a cobweb-like mycelium, but on leaves 
with an uneven surface, and on the stalks of herbs, the mycelium is 
so filamentous and thin as to be scarcely perceptible ; while the erect 
filaments are so numerous as to render the surface downy or hirsute. 
The decumbent filaments are also slenderer than the others, but 
there is no difference in their structure ; they are smooth hyaline 
membranous tubes jointed at distant intervals, the joints alternately 
swollen and constricted, but not regularly so, and when moistened 
with water, the whole tube becomes swollen, tense, and cylindrical. 
The erect filaments are two lines in height, of a gray or cinereous 
colour, with a hoary sporuliferous head ; they are sparingly and ir- 
regularly branched, and at the top four or five short divergent branch- 
lets form a sort of imperfect umbel, collecting, as it were, the sporules 
into a round heap or summit. The main branches are either diver- 
gent or dichotomous ; and many of the filaments are quite simple. 
The sporules are ovate or elliptical, often marked with a septum, 
sometimes transversely, and in others in a longitudinal direction ; 
and this septum disappears when the sporules are moistened. The 
number of sporules is incalculable ; they fall from the head and are 
found adherent to every fibre of the plant; and when this is shaken, 
they fly abroad in a little cloud. 
* Lam. et DeCand. FI. Franc, ii. 71. Duby, Bot. Gall. ii. 921. 
31* 
