INTRODUCTION TO CEYPTOGAMIC BOTANY. 



281 



paratively rare species as Hypoxylon vernicosum are some- 

 times very widely diffused. It occurs in the south of Europe, 

 in North America from Ohio downwards ; and it again turns 

 up in the Himalayas above Sikkim, scarcely altered in form. 

 The insect Sphcerice again occur in very different realms, 

 though not always under the same species. China, Khassya, 

 Australia, New Zealand, the West Indies, North America, and 

 Europe, all produce their kinds, and that upon insects of ex- 

 tremely different affinities. There are other fleshy SphmricB 

 which resemble greatly the insect species, but differ totally as 

 to habitat. We have two species which grow on Elapho- 

 myces, one of them of considerable size, but nothing with a 

 similar habit occurs in the southern hemisphere. One or two 

 similar though smaller species grow upon Ergot, of which they 

 seem beyond doubt to be the ultimate development. To 



Fig. 65. 



a. Spheeria pubis pyrius. Perithecium, aseus, sporidia, and myce- 

 lium, threading the woody fibres of the plant on which it grows. 



1). Sph<Bria amblyospora. Berk, and Br. Section of perithecium im- 

 mersed in bark and sporidia. 



c. Sporidium of Sphmria inquinans, with its appendages, and of 

 Stilhospora macrosperma. 



d. Sporidium of Tuber melanospermum. 



All more or less magnified. 



obtain them it is merely requisite to place the ergot In soil 

 kept moderately damp, but not so damp as to encourage 

 mould, and after a few months there is a tolerable certainty 

 of a crop. 



