276 FUNGI. 



The Tiiberacei* are remarkable amongst the fungi in being 

 all of them more or less hypogeous. They are natives of warm 

 countries, and are distributed into numerous genera and -species. 

 The Tuberacei constitute in Northern latitudes a group of fungi 

 very poor in specific forms. The few species of the Hymeno- 

 gastres belonging to Sweden, with the exception of Hyperrhiza 

 variegata and one example of the genus Octaviana, are confined 

 to the southern provinces. The greater part of this group, like 

 the Lycoperdaceij are met with in the temperate zone. Most 

 examples of the genus Lycoperdon are cosmopolitan. 



The Nidulariacei and the Trichodermacei appear to be scat- 

 tered over the globe in a uniform manner, although their species 

 are not everywhere similar. The same statement applies to the 

 Myxogastres, which are common in Lapland, and appear to have 

 their central point of distribution in the countries within the 

 temperate zone. At the same time, they are not wanting in 

 tropical regions, notwithstanding that the intensity of heat, by 

 drying up the mucilage which serves as the medium for the 

 development of their spores, is opposed to their development, t 



Of the Coniomycefes, the parasitic species, as the Cc&omacei, the 

 Puccmiei, and the UstilagineSj accompany their foster-plants into 

 almost all regions where they are found ; so that smut, rust, and 

 mildew are as common on wheat and barley in the Himalayas 

 and in New Zealand as in Europe and America. Ravenelia and 

 Oronartium only occur in the warmer parts of the temperate 

 zone, whilst Sartvellia is confined to Surinam. Species of 

 Podisoma and Jtwstelia are as common in the United States as 

 in Europe, and the latter appears also at the Cape and Ceylon. 

 Wherever species of Sphceria occur there the SpTueronemei are 

 found, but they do not appear, according to our present know- 

 ledge, to be so plentiful in tropical as in temperate countries. 

 The Torulacei and its allies are widely diffused, and probably 

 occur to a considerable extent in tropical countries. 



Hyphomycetes are widely diffused; some species are peculiarly 



* The Hypog&i are evidently intended here by Fries. 



f- Fries, "On the Geographical Distribution of Fungi " in "Aim. and Mag.. 

 Nat. Hist." ser. 3, vol. ix. p. 285. 



