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gaatrese, of a complete abstraction from light, Hysteranglum 

 nephriticum, B and B., occiuTing perfectly mature at a depth of 

 several inches, and genei'ally in a strong, tenacious clay, through 

 which it would be difficult for it to attain the surface. M. Tulasne 

 combines in one group, which he terms Hymenogastreoe, synony- 

 mous with the Hypogoei of Berkeley, such subterranean genera as 

 produce their spores naked and seated on sporophores, or basidia, 

 which line the interior of irregular cells permeating the mass of 

 the fungus. The gi'eater number of these fungi possess an outer 

 coat, or peridium, others, as Gautieria, are wanting in this respect. 

 They assume commonly a globose form, and mostly possess a more 

 or less distinct base, and are variously attached to a mycelium of a 

 threadlike character spreading beneath the soil, where it forms 

 cottony masses, or unequal strings and cords, variously branched 

 and coloured. The genera Hymenogaster and Hydnangium, 

 provided with a distinct base, adhere to their mycelium by this one 

 point. Gautieria and Octaviania asterosperma present to view 

 also a wide base, and when removed froni the soil draw with them 

 a considerable quantity of a white mycelium mixed with earth, 

 resembling that of the Hymeuomycetes. Octaviania compacta, and 

 the Hysterangia connected with their mycelium by various points 

 of their surface, imbibe nutriment through it in every dii-ection. 

 Here we see the relations of the mycelium to the fungus vary much 

 without affecting its general structure. Hysterangium stolonifcrum 

 grows at the summit of a cord-like mycelium, similar to that of 

 Phallus, adhering to it hj a veiy small part of its peridium. The 

 mycelium of Melanogaster and Rhizopogon is composed of threads 

 varying in thickness, generally of a brown or yellow colour, 

 increasing gradually from their extremities, but, instead of each 

 separately producing a peridium and there stopping, they unite 

 together in numbers, and thus give origin to the fungus. In 

 Rhizopogon luteolus the flattened threads of the mycelium form a 

 dense web or network, each thread of which may be seen to divide 

 at the end and separate into its constituent parts in order to 

 compose the outer envelope. This formation is still better seen in 

 Melanogaster, where, the mycelium being less abundant, its 

 constitutive threads are large, and can be more easily traced to 



