6 THE NORTHERN MICROSCOPIST,. 
because he has through examination been brought into close study 
with them. With few exceptions, such as certain agarics, which 
grow only on leaves in process of decay, there is one thing which 
has a tendency to make the study of leaf fungi not so popular as 
that of larger fungi. It is this: they cannot be determined without 
the help of a microscope. There is a similarity in the external 
appearance of many leaf fungi. That man must have a very 
microscopical eye who would venture to say off-hand whether a 
certain fungus growing on grass were Puccinia graminis (Pers), Puc. 
coronata (Corda), or Dothidea graminis (Fr); but put them under 
a microscope and you at once know the three things just mentioned 
to be as distinct from each other as a roll of sausages, a cottage 
loaf, and a cottage loaf with a crown onit. The fact is, one of 
these forms is ascigerous, that is to say contains its spores in an 
ascus or transparent bag, the other two bear the fruit without any 
external case after the young stage. The microscope often costs a 
considerable outlay ; its manipulation is not comprehensible at a 
glance. Connected with the examination of microscopical fungi 
much more trouble is necessary than merely taking an eye scrutiny 
of a good sized fungus, and so deciding its proper place and name in 
mycology. Nevertheless the extra care needed, and labour expended, 
amply repay the student where time is not an essential desideratum. 
You get in the microscopical forms of fungi some of the most 
beautiful colours and shapes you can possibly wish to have. 
For scarlet vermilion you cannot anywhere surpass the Lecythea 
rose (Lev), for intense black the Phragmidia are good examples, 
_ so also the ripened Xenodochus carbonarius (Schl). ‘The leaf fungi 
certainly are beautiful contrasts as regards colour to the natural 
green of the living leaf on which they happen to grow, and often 
to the tint of the dead leaf. ‘Then as regards shape, what is more 
graceful than the form of some of the ascigerous plants? The 
Erysiphei with their appendages springing from their central body 
are nothing short of magnificent. The SfA@riacei are also grand, 
amongst others Sfh. herbarum growing on the peas, var. pisz as it 
is called, &c. Then look at the Sp. coryli (Batsch). Even to the 
unassisted eye the shapes are good. So also is its ally, Spheria 
jimbriata (Pers). Amongst the non-ascigerous particularly may be 
noted when magnified, the Puccinia malvacearum (Corda) P. 
chrysosplenit (Grev) 4cadium urtice (D. C.). The more sturdy 
shapes areshown in Puc. vince (B.) Puc. prunorum (Link) Puc, umbilict 
(Guep). The aculeate forms we get in specimens not British, 
Puccinia aculeata, Puc. Linkii, Puc. Prostit. Nor should the 
Mucedines be forgotten. Penicillium roseum is graceful indeed 
with numbers of its allies. The /ervonospora genus also. ‘These 
show an amount of elegance worth the study, worth the cost, 
worth the trouble many times repeated, of the enthusiastic admirer, 
