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natural orders. For instance, some of the composite plants, 
spurges, spinach family, convolvuli, and allies of the garden 
pink, as well as others, suffer from this parasite. It is also so 
widely spread that it extends to the North American States 
in one direction, and the Falkland Islands in another. That 
it is a fungus, will be supposed from its mention here ; but it 
belongs intimately to none that we have described, and is in 
itself, so far as Great Britain is concerned, genus and species 
in itself. The name bestowed upon it is Cystopus candidus , 
Lev., the relevancy of which will be seen as I proceed. This 
white rust is composed of a receptacle of thick branched 
threads, inclosing spores arranged in a beaded or monihform 
manner, with a short connecting process between them 
(Plate XIII. fig. 17). The Rev. M. J. B. observes that the best 
way to observe the structure, is to make a thin vertical 
section, which will exhibit not only the necklaces of spores, 
but the ob ovate cysts from which they spring, and the curious, 
irregularly branched, often thick and nodose greenish mycelium. 
Besides this, there are also fine mucedinous threads which 
penetrate deeper into and amongst the tissues of the matrix, 
and resemble the more usual form of mycelium in the Uredines. 
If the ordinary method of taking off a portion from the 
pustule and placing it in a drop of water on a slide, be all the 
process of examination adopted, nothing more will be seen 
than myriads of disconnected, nearly globose, translucent, 
colourless spores, with no indication of the true structure. 
This parasite appears also in patches (not orbicular or 
concentric, but dispersed) on the leaves, stems, and fruit, of 
the common shepherdVpurse (Plate XIII. fig. 16), and on the 
leaves of the goats-beard, scorzonera, and salsify, as well as on 
various other plants. Altogether it is a most interesting 
species, and has of late occupied again the attention of 
scientific men ; but I cannot advisedly enter further into the 
subject here, although the whole paper might have been 
devoted with advantage to the history and mystery of its 
existence, and yet been by no means exhaustive. 
Any one may make himself acquainted with the genus 
Coleosporium with but little trouble, which the acquisition will 
more than compensate. A summer stroll into any locality in 
which the common coltsfoot can be found, will be certain to 
prove sufficient. Let the spot selected be any station on the 
North Kent Railway, for those who reside in town, or even a 
trip to the Crystal Palace and a stroll in the grounds, and 
when the well-known leaves of the coltsfoot are descried, the 
under surface of the first leaf will doubtless give proof of the 
presence of the fungus in question, by the orange spores 
amongst its dense woolly hairs. Sometimes the leaf is almost 
