ON A NEW PARASITIC PLANT. 
173 
Observations on the Mould above described , in a Letter to the Editor , by the Rev. 
M. J. Berkeley , M.A., F.L.S. 
Sir, —I have great pleasure in replying to your communication. 1 regret that 
I am not able to do so as satisfactorily as I could wish, in consequence of there 
being no specimens; hut the drawing is so nicely executed, that, even in the 
absence of any analysis, I venture to pronounce the production new, and a species 
of the genus Mucor. Perhaps at some future time you may be able to procure 
specimens, and if so I should feel greatly obliged by an inspection of them. The 
circumstance of its growing from the stomata is interesting, and perhaps throws 
light upon an anomalous and probably allied species ( Mucor niyrescens, Schum.), 
which forms determinate spots on the living leaves of Rhamnus frangula. Botrytis 
parasitica appears to be produced constantly from the stomata; and from Unger’s 
observations on Hypodermous Fungi, it would seem, that they are generally 
found in the same situation, and in fact are not produced at all in plants destitute 
of an epidermis. This was shown to be the case in Puccinia Graminis many 
years since, by Bauer, in his Analysis of the Blight in Corn. The juices with 
which the stomata in certain conditions of the plant are gorged, afford a fit matrix 
for the development of Fungi, exactly as does the honey-dew for Fumago 
foliorum , which is merely a state of Cladosporium herbarum ; or the sap 
flowing from a wounded Vine for the mycelia, which led to Dutrochet’s important 
paper on the development of Mucedinece. I have myself found a new and very 
interesting species of Mucor during the present summer, on the cut surface of a 
stem of Aucuba Japonica , which had been severely pruned in consequence of 
injury from the winter’s frost. The sap flowed in great abundance, in which 
appeared an ochre-coloured mass of filaments having altogether the habit of a 
Conferva , but which soon produced a crop of sporangia when removed from the 
branch, or when the sap flowed less freely. 
Your plant may be characterised as follows:— Mucor hyphcenes , Berk. 
Floccis sterilibus niveis pulvinatis determinatis; fertilibus longius culis; 
sporangiis globosis sporidia nigra copiosissima effundentibus. 
Forming minute white pulvinate roundish masses about the stomata of the 
living fruit of the Doum Palm in iEgypt. Fertile threads rather few, many 
times higher than the mycelium. Sporangia globose; sporidia black, very copious, 
loosely attached to the heads when discharged, which retain their globular form, 
but are greatly increased in size. 
I am, Sir, 
Your obedient servant, 
Kings Cliffe , Northamptonshire , M. J. Berkeley. 
Oct. 9, 1838. 
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