SPOROTRICHUM 107 



Scopulariopsis. This group contains members which were formerly 

 included with Penicillium, but which differ even more markedly than 

 the above. They may form Penicillium-like branching systems (but 

 frequently the branching is irregular) or the conidiophore may re- 

 main unbranched. The terminal branches which form the spores 

 may not be constricted at their apex to a narrow tubular process, as 

 is characteristic of Penicillium. And finally the large, thick-walled, 

 spiny conidia with their ring at the base (Fig. 56) are quite different 

 from those of Penicillium. Species of this 

 genus are the imperfect stages of one or 

 more genera of perfect fungi. 



Scopulariopsis brevicaulis (formerly Pen- 

 icilliu7n brevicaule) is a common species 

 of some importance. The spores are yel- 

 lowish brown in color. It is important as 

 a cause of spoilage of various substances. 

 Growing more slowly than many other 



molds, it takes part in the final disinte- 



,• p ,, 1 I Ti • X- Fig. 56. Scopulariovsis 



gration oi the product. It is very active , . ,. .... 



7 . - brevicaulis: comdiophores 



m proteolysis, producing ammonia abun- ^.^^^ conidia. 



dantly in gelatin cultures. In the presence 



of sugars, it produces from arsenical compounds a substance, di- 

 ethylarsine, which has a very characteristic garlic-like odor. This 

 reaction has been used as a test for arsenic, the reaction being said 

 to be more delicate than the usual chemical tests. Only arsenous 

 acid or its salts of the alkaline metals may be detected readily, salts 

 of the heavy metals not so surely, and arsenic sulphide not at all. 

 But disagreeable odors may be produced on other substrates, de- 

 scribed as ammoniacal, or like turnips or cabbage. According to 

 Thom it is an important secondary invader and cause of spoilage of 

 Camembert cheese and other dairy products. It may be found, along 

 with other molds, in corks, and may give rise to very disagreeable 

 odors in bottled products which have been stoppered with such con- 

 taminated corks, without any evidence of mold growth in the product 

 itself. Various strains similar to S. brevicaulis have been isolated 

 from cases of infection about the finger nails (onychomycosis) ; that 

 they are really pathogenic is doubtful. 



Sporotrichum. The genus Sporotrichum is characterized by the 

 formation of its rather small, round, oval, or pear-shaped conidia 

 sessile on the mycelium or on very small conidiophores, not in chains 

 but in clusters. The conidia arise laterally and at the tips of the 

 conidiophores or hyphal strands from all parts of the mycelium. A 



