44 BWtlSa 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 GymnoascacecB — than which the species are much more highly developed — and the Discomycetes, with which they have no very close affinity, instead of next to the Pyrenomycetes, 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 Hysteria cccb, 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 Phacideacea, which are placed at the commence- ment of the Discomycetes, the Hysteriacea 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- mycetes, and next to the Pyrenomycetes ? The Sticte(B would then lead on in a natural sequence from the GymnoascacecB to the higher families of the Discomycetes, the last of which, Helvellea, 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 Barlcea, which is only Humaria with globose spores, — surely not a sufficient generic distinction ; and Mitrophora, although a genus instituted by Leveille, 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, Hymenoscyi)ha being merged into Belotium, with the addition of some few species formerly arranged under other genera. This is well, and a study of the analytical table to the Glabratce section of Pezizce 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.
