50 
tion, requiring for the determination of their structure and 
place in classification the patient use of the microscope . 1 The 
group is a most heterogeneous one, comprising many genera 
and species that are at least anomalous : 2 that have been im- 
perfectly studied : and that are comparatively little known. 
There are several advantages, I think, from bringing 
them together and studying them in a group. I believe 
that a satisfactory study will result in a great reduction of 
their generic and specific names. The present names — 
• — generic especially — must be considered as only provisional. 
As matters stand, different names are probably given to the 
same parasite as it grows on different Lichens. It will be 
found, moreover, I doubt not, that the number of Lichens of 
the lower groups ( e . g. in the single genus Lecidea, or its 
numerous and varied sections or sub-genera) which occur in 
an athalline parasitic form are more numerous than we at 
present suppose. 
Various members of the group of micro-parasites enume- 
rated in the following list should rather be transferred to the 
provisional family of Fungo-Uchens , 3 and may ultimately be 
claimed as Fungi proper. The difficulty of separating the 
lower Lichens from the lower Fungi is, however, daily be- 
coming greater and greater . 4 The old diagnostic of the 
Nylander or other authorities, who regard Lichens as mere Epiphytes. I have 
elsewhere pointed out (“Is Lichen-Growth detrimental to Forest and Fruit 
Trees?” ‘Report of the British Association,’ 1S67, p. 87) that the faorganic 
constituents of the Lichen-thallus prove Lichens to be as truly parasitic as are 
the lower Fungi. The distinction drawn, therefore, by Haliier (pp. 215 and 
217) between Lichens and Fungi, as being in the one case“echteepiphyten” 
and in the other “ echte parasiten,” is not true to nature. Korber 
designates the group of athalline Micro-lichens here enumerated “ Lichenes 
Parasitici ; Pseudo-lichenes, Auct.,” and describes them in an appendix. 
But the designation in question does not apply more properly to this 
interesting group of microscopic Lichens than it does, e.g. to the corti- 
colous species of the genera Eoernia, Ramalina, Usnea, Lecanora, Lecidea , 
or Verrucaria. His group is, moreover, most heterogeneous, for he includes, 
e.g. Lecidea resince, Fr., which occurs directly on the bark, as well as its 
resinous exudates, of various Coniferse; and which, moreover, is classed 
among Fungi by Fries, Nylander, and Berkeley. 
1 Vide also the .author’s ‘ History of British Lichens,’ p. 309, and Ny- 
lander’s ‘ Synopsis Methodica Lichenum,’ p. 58. 
2 Korber (in his ‘Parerga Lichenologica,’ 1865, p. 452) classes them 
separately as “ Lichenes parasitici while they constitute the “ Pseudo- 
lichenes ” of Krempelhuber (‘ Lich. Flora Bayerns,’ p. 86) and other authors. 
3 Anzi, in his ‘ Symbola Lichenum rariorum vel novorum It alias 
superioris,’ 1866, enumerates as “inter Lichenes et Fungos ambiguse” 
species of the genera Abrotliallus, Conida, Phacopsis, Celidium, Arthonia, 
Xenospherria, Phceospora, and Tichothecium. 
4 Vide the author’s paper on Arthonia melaspermella, ‘Journ. Linn. 
Society,’ Botany, v. ix ; and ‘ N. Z. Lich. and Fungi,’ Trans. Royal Society 
of Edin., vol. xxiv, pp. 423, 434. 
