58 MICEOSCOPIC FUNGI. 



termed a genus j and tlie term prefixed to the specific 

 name of each, species constituting that genus is its 

 generic name^ also commonly derived from the 

 Latin or Greek. In this instance it is Pucciniaj 

 derived from the Greek puJcaj meaning closely 

 ' packed, singularly applicable to the manner in 

 which the spores are packed together in the pus- 

 tules. The common features^ or generic distinc- 

 tions^ of this genuS; are uniseptate spores borne on 

 a distinct peduncle. 



In returning to the species found on Labiate 

 plants^ let us suppose ourselves to have strolled 

 towards Hampstead Heathy and south of the road 

 leading from Hampstead to Highgate,, near certain 

 conspicuous and well-known arches,, built for a pur- 

 pose not yet attained^ are two or three muddy 

 ponds nearly choked up with vegetation. Some 

 fine autumnal afternoon^ we must imagine ourselves 

 to have reached the margin of the most northern of 

 these pondS; and amidst a thick growth of reeds^ 

 sedges^ and other water-loving plants^ to have 

 found the water-mint in profusion and luxuriance^ 

 with every leaf more or less occupied^ on its under 

 surface^ with the yellow spores of a species of rust 

 (Trichohasis) mixed with the browner septate spores 

 of the mint brand {Puccinia Menthce) . This is com- 

 mon also on the horse-mint and corn-mint ; we 

 have found it on the wild basil and wild thyme^ 

 and once only on marjoram. Having collected as 

 many leaves as we desirCj and returned to home 



