16 TRANSACTIONS, NATURAL HISTORY SOCIETY OF GLASGOW. 



Tweed, Forth, Clyde, Tay ! Argyle, Dee! Moray. 

 Eiif^land, Europe. 



20. M. Grossulariae (Wallr.) Lev. (M.S ). - On 

 leaves of Rihes Grofisidaria, in autumn. 



Tweed, Forth, Clyde, Tay! Argyle, Dee! Moray, 

 Ross. 



England, Europe, Siberia, N. America. 



21. M. Alni (D.C.) Winter {M. penicillata Lev., 

 M.S. 1833, and J/. Heduigii Lev., Scot. Nat. vol. VI., 

 p. 165). — On leaves of Viburnum Opulus !, towards the 

 end of summer and in autumn. 



Tay ! Argyle, Dee ! 



England, Southern and Central Europe, N. America. 



I am. not aware that this species has been found in Scotland 

 on any other host-plant than F. Opulus, as I have been 

 informed that "alder" noted for it in J/.yc. Scot, should have 

 been "guelder-rose"; but I have gathered it on Alnus incana 

 in Norway, and careful comparison of the Norwegian examples 

 with M. Hedu-igii from near Aberdeen and from Kenmore in 

 Perthshire has led me to believe that there is no good specific 

 distinction between the two. So, in like manner, I have been 

 unable to distinguish between M. Hechviyii and M. jyenicUlata 

 by any constant difference ; so that I agree with the view that 

 the three must be regarded as forms of one species. 



A considerable number of Scotch Phanerogams, in addition 

 to those mentioned above as host-plants of Erysipheae, bear 

 forms of OifZniJH, the mycelia of fungi belonging to this group; 

 but I have not succeeded in detecting perithecia upon them, 

 and am therefore vmable to assign them with confidence to 

 their several species. Among the favourite hosts are Pofentilla 

 Toriuentillal Alchcmilla arvcnsis\ Seiiecio vulgaris I S Jacobueal 

 and cultivated Chrysaiitheinunis ! 



The following species of Erysipheae should be 

 looked for in Scotland, as it is not improbable that 

 some of them may yet be discovered here : 



Sphaerotheca Nieslii Thum., on Pyrus Aria. 



S. detonsa (Fr.) Kickx, on Apargia, in Belgium, 

 and on Tanacetuni, in the Vosges. 



S. fugax Penz. and Sacc, on Geranium silvaticum, 

 in Northern Italy. 



Podosphaera Schlechtendalii Lev., on Salix alba 



