Rev. M. J. Berkeley on British Fungi. 359 



I have an authentic specimen, as also French specimens from 

 Messrs. Tulasnc, differs in its large cells and in other particulars. 



Choiromyces, Vitt. 1. c. p. 50. " Uterus polymorphus, sessilis 

 arrhizus 1. basi absorbente prseditus, extus l8e\is vel spongioso-ver- 

 rucosus interne carnosus solidus ; caro venis seminiferis variegata. 

 Asci longissime pedicellati, 1. breviter pedicellati oblongo-elliptici 

 lagenseformes octospori, simplici serie ad latera venarum distri- 

 buti. Sporidia sphserica echinulata." Vitt. (paucis mutatis). 



319. C. melanoxanthus, Tul. MSS. Minor angulato-globosus, 

 basi absorbente manifesta; externe niger spongioso-verrucosus, 

 interne ohvaceo-flavus, venis fructiferis nigris. Bowood Park, 

 Wilts, October, C. E. Broome, Esq. 



About the size of a horse-bean, globose, but more or less com- 

 pressed and angular, furnished with a distinct absorbent base. 

 Externally black, clothed with obtuse but not rigid warts, which 

 are less manifest when the plant i^ dry. Flesh of a dirty olive- 

 yellow with broad black veins, which consist of a loose slightly 

 branched tissue arising from hexagonal cells, the ends of the 

 threads of which become oblong-elliptic, distinct, pechcellate asci, 

 containing eight dark, globose, echiuulate, but not reticulate spo- 

 ridia. Smell in some specimens like that of some agaric, in others 

 strong and rather nauseous. 



This very interesting species was communicated by me to 

 Messrs. Tulasne under the name of Tuber melanoxanthum, with 

 the remark however that the genus required revision, as this spe- 

 cies and some others differed in structm-e fi'om the real Truffles. 

 I received from them in return French specimens under the MS. 

 name of Choiromyces viridis, for which, with their permission, I 

 have substituted the name of C. melanoxanthus. It differs con- 

 siderably in habit and colom* from the other known species, and 

 further researches may perhaps make it necessary to separate it. 

 Mr. Broome has found another species of Choiromyces belonging 

 to the same group as C. mceandriformis, but unfortunately in too 

 young a state to ascertain exactly its characters. 



320. Tuber melanosporum, Vitt. 1. c. p. 36. Budloe, Wilts, 

 C. E. Broome, Esq., October to January. 



A very distinct species from the common truffle, but in some 

 states difficult to distinguish. When fresh the warts are of a 

 bright brown, showing in the interstices the pale tint of the inner 

 substance ; in drying however the brown tint is entirely lost. The 

 sporidia are small, elliptic, ciliated, but I believe not reticulated. 

 The veins are very broad with narrow interstices. Smell very 

 different from that of Tuber astivum, at length rather disagreeable. 

 The largest specimens that have at present occurred do not ex- 

 ceed f ths of an inch in diameter. 



321. T. nitidum, Vitt. 1. c. p. 48; Berk. Brit. Fung. Fasc. 4. 



