ON THE \YIIITE RUST OF CABBAGES, 267 



Capparideae, Amaranthacese, and possibly on species of some otlier 

 families to which I cannot at present refer. Its geographical 

 range is also most extensive, extending in the northern hemisphere 

 from high latitudes as far south as South Carolina, and it occurs 

 in the Falkland Islands on Arabis Macloviana. It is besides 

 frequently accompanied by Botrytis parasitica, which there is 

 much reason to believe is sometimes as pernicious as its near 

 ally B. infestans. 



It was in a species of the last-mentioned natural order (Ama- 

 ranthaceae) that in the spring of the pi'esent year my attention 

 was first turned, on the examination of specimens received from 

 the R«v. M. A. Curtis, of Society Hill, South Carolina, to the 

 peculiar structure of this parasite, and my observations have 

 been at once confirmed and anticipated by my excellent friend 

 Dr. Leveille, in an arrangement of Uredineag, in a late number 

 of ' Annales des Sciences Naturelles,' which bears date Dec. 

 1847, but which was not published till some months later. 



There was no difficulty at the time in procuring fresh speci- 

 mens for examination, for so early as the end of March not a 

 cabbage or colewort in my garden was free from the white rust ; 

 and as the season advanced, the young as well as the nearly ma- 

 ture plants became affected, presenting frequently a disagreeable 

 leprous appearance, deranging their growth, and sometimes ma- 

 terially affecting their produce. At length, in the month of 

 June, the flowering plants exhibited the disease to an extra- 

 ordinary degree, and became so strangely distorted, that on a 

 cursory inspection it would have been difficult to say to what 

 species a gathered specimen belonged. Every part of the flowers 

 had become immensely enlarged ; the leaves of the calyx and 

 petals assumed a gigantic size, the latter retaining in some mea- 

 sure their proper yellow tint ; the stamens too were distorted, 

 and the pistil projected beyond the now persistent blossom, and 

 instead of being as usual narrow, was a quarter of an inch 

 or more in width, and very much compressed on the sutural 

 side, and on opening the young carpels, their inner surface, and 

 in some cases even the placenta, was infested with the white 

 spots of the rust. In some cases every flower and pod was 

 affected, in others the mischief was confined to two or three 

 upon a stalk, so as not to prevent entirely the production of 

 seeds. Nothing indeed could well present a more singular ap- 

 pearance than the plant with its swollen and distorted leaves, its 

 occasionally abortive panicles, of which nothing remained but 

 roselike tufts formed by the gouty stem-leaves, and above all 

 the powdery heads of buds and the pendent fleshy flowers as 

 large as those of Alhuca major, and with somewhat of the same 

 green and yellow aspect. 



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