1 66 Scientific Proceedings, Royal Dvhlin Society. 



Sorosporium Scabies. Fearing that I had made a serious mistake, a,nd 

 identified as a slime-fungus an organism which was regarded by Massee and 

 earlier observers as a smut, I restored the scrap of type-material and examined 

 it, to find that it agreed in all respects with my material, that it showed no 

 trace of any Ustilagineous characters, and that it was identical with the 

 slime-fungus Spongospora Solani. I wrote to Kew to tliis effect, and inserted 

 the following paragraph at the end of my paper : — 



"Through the kindness of Colonel Prain, f.r.s., the Director of the 

 Royal Botanic Gardens, Kew, I have been able to compare type-herbarium 

 material of Sorosporium Scabies (Berk.), Fischer de Wald., with Spongospora 

 Solani, Brunch. I can see no difference in size or structure of tlie spore- 

 balls of the two, and believe microscopic examination of restored material will 

 show that Sorosporium Scabies, with its ' glomerulis 1-2 lacunosis,' should be 

 removed from the Ustilaginese — that it is really Spongospora Solani." 



Massee evidently accepted my view, since a few months later, under the 

 heading " English Potato Scab," it is stated in the Journal of the Board 

 of Agriculture (England), vol. xv., p. 509, that " in 1886 Brunehorst described 

 a destructive organism on potatoe.? as Spongo.spora Solani, Brunch., and this 

 species was in reality the pest previously named by Berkeley, although 

 not recognized as such by Brunehorst." My recognition of the identity is 

 ignored, and the name proposed is Spongospora Scabies, Massee. 



Under this name the "Corky-scab," as I liad named it, is described in 

 detail in the November number (5) of the Journal (vol. xv., p. 592) with a 

 plate of illustrations. To this paper I shall return. 



Berkeley's (6) first account of the scab is illustrated by two small figures of 

 the spore-ball of the fungus, each with a short stalk of attachment. Was 

 there anything to account for these stalks ? The spore-balls appear to me 

 to lie free in the cavities of the cells, and to show no trace of a stalk. The 

 shrivelled remains of the host- cell cling to the ball sometimes, and might be 

 mistaken for a stalk. It is clear that Berkeley gave little attention to this 

 scab, as he was fully occupied with the " murrain." Thus, in the article on 

 the murrain, he writes (p. 33) : " Amongst the diseases noticed by Martins is 

 one which he considers as depending on a species of Protomyees. As I 

 have seen this iu various stages of growth, and attached to its flocci, I have 

 thought it worth figuring. It appears to me to belong to the genus 

 Tuburcinia, Fr. The spores have usually one or more cavities in the surface 

 communicating with the interior cavity. They piay, perhaps, therefore be 

 considered rather compound bodies, consisting of a quantity of cells arranged 

 in the form of a hollow ball. This view of their structure requires more 

 attention than I am able to give to it at present . . . ." (p. 10). "Another 



