544 PATHOGENIC- FUNGI 



varieties — a large-spored and a small-spored form, the former 

 being the more frequent. Both in the tissues and in cultures 

 the chief elements are double-contoured, septate mycelial 

 threads, — the elements being of varying sizes, — and round or 

 oval spores (in the large-spored type 5-6 /x long and 4 p broad). 

 The fungus grows readily on artificial media, especially those 

 containing beerwort (p. 53), and while some varieties liquefy 

 gelatin, others do not. In the case of the latter, the superficial 

 colonies on gelatin are granular with peripheral feathery ex- 

 tensions, while the deep colonies are rounder and more circum- 

 scribed. The colour is white or slightly red, and the cultures 

 have a sourish alcoholic smell clue to the production of aldehyde, 

 alcohol, and acetic acid ; glucose, lsevulose, and maltose are 

 slowly fermented, but the fermentation reactions differ in differ- 

 ent species of monilise. On ordinary media, mycelium and 

 spore production are seen, the former being especially marked in 

 deep colonies. Chlamydospore formation is also stated to occur, 

 and from such elements on a mycelium, free conidia formation 

 takes place. 



Aspergillosis. 



In 1856, Virchow recorded several cases of affection of the 

 lungs by aspergilli, and a number of similar cases have since 

 been described ; usually there has existed some other disease iu 

 the body, and frequently the lung has also been the site of 

 tuberculosis. The appearances presented are those of small grey 

 nodules, composed of necrotic material and leucocytes, breaking 

 down to form cavities associated with areas of broncho-pneumonia, 

 and frequently also with fairly widespread odourless necrosis 

 of the lung. Masses of fructifying mycelia are present in the 

 cavities and extend into surrounding bronchioles and air cells. 

 The condition has usually been discovered post 'mortem, but in 

 certain cases the fungus has been observed in the sputum during 

 life, and it is probable that a lung condition of this kind can 

 be recovered from. A similar affection occurs in birds. It is 

 probable that infection arises from inhalation. The variety of 

 organism chiefly present is the Aspergillus fumigatus (cf. p. 534), 

 which on artificial media gives a greenish-blue colour resembling 

 that ef the Penicillium crustaceum. Its optimum temperature is 

 that of blood heat. 



Infections with aspergilli also occur in the external ear as 

 a chronic pustular condition of the epithelium, and aspergillary 

 colonies are also from time to time observed on abrasions of the 



