44 BRITISH FUNGUS FLORA. 



granting that a perfect linear arrangement of groups of natural 

 objects is an impossibility, it is difficult to understand why this 

 family has been placed here, between the GymnoascacecE — than which 

 the species are much more highly developed — and the Discomtjcetes, 

 with which they have no very close affinity, instead of next to the 

 Pyrenonujcetes, a family closely related in structure of ascophore 

 and spores, and of similar habitat ; the principal difference being 

 in the longitudinal dehiscence of the ascophore in Hysteriacccr, as 

 compared with the pore-like orifice of many of the Pyrenomycetes. 

 As regards the spores, it is probable that every species of the one 

 family might find a place in close relationship with those of the 

 other. With the Phacideacem, which are placed at the commence- 

 ment of the Discnmycetes, the HysteriacecB have much in common, 

 and therefore would it not be better to consider these as a new point 

 of departure, and to place all three groups after the rest of the Disco- 

 viycetes, and next to the Pyrenomycetes.^ The Stictea; would then lead 

 on in a natural sequence from the GymnoascacecB to tlie higher families 

 of the Discomycetes, the last of which, HelveUecp, ends the volume. 



Each family is preceded by an analysis of the genera, the names 

 of the older mycologists being retained, and where subdivision of 

 genera has been found necessary, old names have been restored, or 

 more modern ones adopted. In some few cases these names seem 

 to have been unnecessarily multiplied, as in the case of Barlaa, 

 wliich is only Eumaria with globose spores, — surely not a sufficient 

 generic distinction ; and Mitrophora, although a genus instituted by 

 Leveill6, might well have remained united to Morchella, it being 

 unnecessary to divide such a small and well-defined group into two 

 genera, solely on account of the margin of the pileus being adnate 

 in one section and free in the other. In such a comparatively 

 limited fungus-flora as that of Britain, it would be well to cut down 

 the number of generic names as much as possible, and not to follow 

 too closely in the steps of those European mycologists who have 

 manufactured genera to such an extent as to lead to the belief that 

 at no distant date each species will be a genus in itself. 



Mr. Massee, however, does not always accept such refined dis- 

 tinctions as those noticed above, but has in at least one instance 

 united instead of divided genera, Hymenoscypha being merged into 

 Helotiiim, with the addition of some few species formerly arranged 

 under other genera. This is well, and a study of the analytical 

 table to the Glabrata section of PezUm will show that the genus thus 

 constituted is separated by sufficiently definite characters from its 

 neighbours. In most of the other genera described in this work, 

 the species have been so grouped into sections that the labour of 

 hunting down a plant is reduced to a minimum ; but in this genus 

 the only assistance afforded to the student is that they are grouped 

 according to habitat. This, taking into consideration the author's 

 remark in connection with the generic description, is useful and 

 perfectly legitimate ; but some kind of analytical key to the species 

 would have been very acceptable in a genus containing seventy 

 species, which in some of the groups are with difficulty distinguished, 

 especially in the case of dried specimens. 



