144 PRACTICAL MICROSCOPY. 



The illustration Fig. 127 shows a section of chalk from 

 Gravesend with Foraminifera in situ. 



Amongst others, Lagena squamosa, Orbitolites compla- 

 natus, Polystomella crispa, and Nodosaria raphanus, are 

 very good objects. 



Books which may be consulted: Williamson's ' Recent 

 Foraminifera ' (Ray Society) ; Carpenter's ' Introduction 

 to the Study of Foraminifera.' 



FUNGI. Micro-fungi may be found everywhere, and 

 make a splendid study. Many of them, however, can only 

 be examined successfully when in the fresh state, such as 

 Penicillium crustaceum and Aspergillus glaucus, the common 

 moulds and mildews of our houses. Nearly every plant 

 and tree is attacked at one time or another by some parti- 

 cular species of micro-fungus, so that the student will find 

 plenty of work in this class alone. We have the Puccinia 

 graminis upon the leaves and stems of standing corn, as 

 well as Tilletia caries and Ustilago segetum or smut, which 

 fill up and destroy the whole contents of the ear ; the 

 JEcidium on the berberry bush ; Triphragmium on the 

 leaves of the meadow-sweet ; the blackberry brand, Aregma 

 bulbosum; Coleosporium synantherarum on the colt's-foot ; 

 Cystopus candidus on cabbages ; Peronospora infestans on 

 our potatoes ; Peronospora gangliformis on lettuces ; and 

 Peronospora vici<z on peas : a host of others being within 

 easy reach. 



The micro-fungi shown in Fig. 128, are as follow: 



a. Stachybotrys lobulata. 



b. S. atra. 



c. Penicillium sitophilum (Oidium aurantiacutn). 



d. Myxotrichum deflexum. 



e. Polyactis fascicularis, 



f. Sporocybe alternata (Aspergillus alternate). 



g. Rhopalomyces pallidus. 



h, Papulaspora sepedonioides. 

 i. Acremonium alter natum. 



