BULLETIN OF THE BUSSEY INSTITUTION. 4138 
ab eadem, maxime si fortuito ea aruerit, frustulatim aliquando secedat. 
Id cuticulz struunt utriculi, perexigui, . . . oleo pallido tandem re- 
pleti,’ &c. This initial stage described by Tulasne is figured in ‘Table 
XXXIV., Fig. 2, mm., 1. c. We must confess that the expression, 
“matricique vive instar gummi soluti illitus heret,” seems a little 
indefinite, but the figure looks exceedingly like a collection of oil- 
globules, or very small eggs. We do not pretend to say that what 
Tulasne saw was not a membrane of vegetable substance, — a part of 
the fungus itself; but, in the Californian specimens, we had some- 
thing which looked very much like the mm. of Tulasne’s figure, and, 
in this case, we have satisfied ourselves, by observation and experiment, 
that it is of animal nature, and not a part of the fungus, which, in- 
stead, was growing upon it. It is a little difficult to understand, from 
what is already known of the development of fungi, how any fungus 
could begin as a very thin membrane, composed of small cells filled 
with oil. The initial stage of fungi, if we except the Myxomycetes, 
as far as we know, is filamentous, not membranous. 
The result of our examination of the diseased orange and olive 
leaves is briefly as follows: The disease, although first attracting the 
eye by the presence of a black fungus, is not caused by it, but rather 
by the attack of some insect, which itself deposits some gummy sub- 
stance on the leaves and bark, or so wounds the tree as to cause some 
sticky exudation, on which the fungus especially thrives. It is not 
denied that the growth of the fungus greatly aggravates the trouble 
already existing, by so encasing the leaves as to prevent the action of 
the sunlight: we only say, that, in seeking a remedy, we are to look 
further back than the fungus itself, — to the insect, or whatever it may 
be, which has made the luxuriant growth of the fungus possible. 
With regard to the fungus, we are able to assert that it is the same 
on both olives and oranges, — the species described by Berkeley and ~ 
Desmazieres under the name of Capnodium Citri, which seems to us, 
together with the pycnidial state described by Montagne under the 
name of Antennaria eleophila, to be but two states of a species iden- 
tical with that described by Tulasne as Fumago salicina, It remains 
yet to find the asci on olives or oranges, which will probably be ac- 
complished without difficulty in California. The earliest stages of the 
fungus should be studied by some one living near orange-groves ; for, 
although the disease has been known to attack greenhouse plants, it is 
