28 Massee—A Monograph of 
produced as in Hymenogaster ; hence, if the above account is 
correct, the Gastromycetes have been derived from the Asco- 
mycetes through the Tuberaceae, by the gradual conversion of 
asci into basidia. The evolution of the Hymenomycetes from 
the Ascomycetes, through the Uredineae, first pointed out by 
De Bary, is now generally accepted ; and it may be urged 
against the above idea, that it is improbable there should be 
two independent starting-points for the Basidiomycetes ; yet 
it may perhaps not be more improbable than that there should 
be two independent formations of the hymenium, etc., by 
differentiation in the interior of the primordial coil of hyphae 
at widely separated points in the Hymenomycetes, as stated 
by De Bary. 
Distribution. 
There are about six hundred known species belonging to 
the Gastromycetes, of which two hundred are European. In 
Great Britain we have twenty-one genera, including seventy- 
four species, which is rather poor compared to the numbers 
found in France and Germany, the former having one hundred, 
the latter one hundred and five species. 
The Phalloideae, numbering about seventy-four species, are 
mostly tropical or subtropical, but extending in numbers 
further south than north. There are four known European 
species, three of which are British. Clathrus cancellatus reach- 
ing its northern limit on the south coast, Ithyphallus impudicus 
and Mutinns caninus reach the north of Britain, the former 
extending to North America and Japan. The extra-British 
species, Colus hirundinosus , is in Europe confined to the south 
of France and Spain, and has been collected in Algeria, West 
Australia, and Cayenne. 
The Hymenogastreae, as would be expected from their 
subterranean habit, have only been collected where specially 
looked for, and are up to the present most abundant in western 
and central Europe ; our own twenty-three species being 
largely due to the researches of Berkeley and Broome. 
