MICROSCOPIC OBJECTS. 46 



Fig. 91. Bramble-leaf Brand (Aregma bulbosum), x 350. 



This, together with many other objects mentioned in this 

 book, are not at all uncommon, and for that very reason I 

 have taken it ; so that it may be seen that the rarest objects 

 are not always the most beautiful, nor yet even the most 

 instructive. 



The reader has, no doubt, often noticed in the autumn that 

 the leaves of the Bramble are spotted with small black dots ; 

 these dots, when magnified, resolve themselves into a number 

 of oblong spores seated on stalks. These spores appear to 

 be divided into three or more cells, and they may be taken 

 as an example of the general structure of the brands, which, 

 although not so destructive as the Rusts &c., still in some 

 cases do much harm to the farmer's crops. 



The best plan of mounting these brands is to cut a very 

 thin section through the leaf containing the brand, and then 

 to mount it in a shallow cell in the essential oil of lemon. 



Fig. 92. Cluster-cups on the Leaf of the Pilewort (^Ecidium 

 Ranunculacearum) , x 20. 



Cluster- cups are another kind of microscopic Fungi, also 

 common on many of our British plants ; for instance, on the 

 Common Spurge (Euphorbia amygdaloides) of our hedges 

 they will be noticed in large numbers. To make out their 

 structure, the leaves on which they grow may have sections 

 cut through them, and also the cuticle of the leaf may be 

 torn off. The spores are large in most of the species, and 

 when young will be seen seated in the cups, or, as they are 

 called, the peridia. 



These objects, when entire, are best when mounted dry ; 

 but the sections &c. are best mounted in fluid. I prefer oil 

 of lemon. 



