CLUSTER-CUPS. 6 



some knowledge of tlieir generic and specific dis- 

 tinctions. 



It is exceedingly difficult to give a logical defi- 

 nition of what constitutes a fungus. It is no less 

 difficult to furnisli a popular description whicli shall 

 include all and nothing more. If, for example^ we 

 particularize the spots and markings on the leaves 

 and stems of herbaceous plants^ so commonly met 

 with from early spring till the fall of the last leaf, 

 and even amongst the dead and decaying remains 

 of the vegetation of the year_, we may include also 

 such spots and marks as result from insect depre- 

 dations or diseased tissue. It is not always easy, 

 with a cursory observation under the microscope, 

 to determine whether some appearances are pro- 

 duced by fungi, insects, or organic disease : expe- 

 rience is the safest guide, and until we acquire that 

 we shall occasionally fail. 



If we take a stroll away from the busy haunts of 

 men, though only for a short distance, — say, for 

 example (if from London), down to New Cross, 

 — and along the slopes of the railway cutting, we 

 shall be sure to find the plant called the goatsbeard 

 [Tragopogon loratensis) in profusion. In May or 

 June the leaves and unopened involucres of this 

 plant will present a singular appearance, as if 

 sprinkled with gold-dust, or rather, being deficient 

 in lustre, seeming as though some fairy folk had 

 scattered over them a shower of orange-coloured 

 chrome or turmeric powder. Examine this singular 



B 2 



