318 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1945 



especially in Great Britain. Many of the ringworm group are able to 

 live parasitically on domestic animals ; some are known to live sapro- 

 phytically on organic debris, and others have been reported as capable 

 of infecting living plants. Athletes' toe {Trichophyton spp., Epi- 

 dermophyton) has become increasingly common in Great Britain dur- 

 ing the past few years and is prevalent in certain sections of the fight- 

 ing services. But there are many less obvious diseases which have been 

 studied principally in France and America. That they exist elsewhere 

 is shown by the recent recognition of histoplasmosis {Histoplasma 

 capsulatum) in Great Britain. The symptoms of this disease are pro- 

 tean; they may simulate kala azar or pulmonary tuberculosis — and 

 the prognosis is bad. A recent discovery by C. W. Emmons that small 

 desert rodents constitute an important natural reservoir of Coccidi- 

 oides immitis, the cause of coccidioidal granuloma, is of importance. 

 This disease has been known for about half a century in North and 

 South America and was thought to be soil-borne. The Medical Re- 

 search Council has recently appointed a committee to report on the 

 situation of medical mycology in Great Britain. 



Animals other than those domesticated are also liable to fungal dis- 

 ease. Insects particularly are affected, whole groups of fungi being 

 entomogenous ; as, for example, the Laboulbeniales with about 120 

 genera and 1,500 species, so well monographed by Thaxter. Moreover, 

 it has been shown recently by C. Dreschler that there are a number of 

 species, Entomophthoraceae and Hyphomycetes, which parasitize nem- 

 atodes, amoebae and other small soil inhabitants. 



The extent of the damage by fungi to stored products of all kinds 

 is only gradually being realized. The losses in textiles have received 

 most attention and the investigations of the conditions in which cotton 

 and wool become mildewed are influencing the practices of manufac- 

 ture. The methods of preserving foodstuffs — sterilization, canning, 

 pickling, and so on — are chiefly to prevent mold attack, though they 

 also protect them from bacterial contamination. 



The outward and visible sign of specific differences in fungi is 

 morphological as in green plants and animals, but this should not mask 

 the fact that a given species growing under definite conditions always 

 acts in the same way and brings about the same results. Can we so 

 harness any species that it will produce results useful to us ? What has 

 Nature herself done in this direction ? 



Armillaria mellea is a common toadstool which causes a good deal 

 of disease in trees but is also able to live saprophytically. It spreads 

 by means of rhizomorphs, strands of compacted mycelium which look 

 somewhat like flattened, branched, and anastomosing black leather 

 bootlaces. If these encounter potato tubers, they reduce them to 

 mush in 2 or 3 days. On the other hand, if the rhizomorphs meet the 

 tubers of the Japanese saprophytic orchid Gastrodia elata^ they pene- 



