308 DR. LINDSAY ON WEST-GREENLAND LICHENS. 
land, where none of its species have yet been found, save a parasite which I 
assign to it doubtfully *. The truth is, that Isidiwm is a condition of. several 
saxicolous species, both of Pertusaria and Lecanora, and probably also of 
Lecidea t. 
: (d) Growth of warts or tumours, sometimes spherical, and ultimately detached or 
detachable, e. y. in Lecanora ventosa and L. tartarea. 
(e) Excessive development of the gonidic element in the form of soredia, consti- 
tuting the pseudo-genus Variolaria. 
(f) Dwarf states, especially where the thallus is fruticulose, e. y. in Stereocaulon and 
Cladonia. 
5. Abnormalities of colour, e. y. the colour-mottlings of the podetia of Cladonia. 
6. Unusual habitats. 
(a) Other, generally higher, lichens, especially when old, decayed, and bleached 
by the weather, e. g. :— 
(L) Parmelia saxatilis on the scyphi of Cladonia pyxidata, nid on the thallus of 
Umbilicaria vellea. 
(11.) Physcia pulverulenta and stellaris on the thallus of the same Umbilicaria. 
(ILL.) Lecanora sophodes on Umbilicarie and Cladonie. 
(IV.) Lecidea myriocarpa on Umbilicarie. 
(5) On dried excrement of animals, e. y. Lecanora polytropa on that of birds. 
(c) On the bleached bones of dead animals, e. y. Squamaria saxicola on the vertebræ 
of Whales. 
7. Athalline conditions: the apothecia constituting the entire plant, and growing | 
parasitically or not, e. y. Lecidea parasema, vernalis, and myriocarpa. 
8. Variation in the character of the sporidia in the same species, e. y. Lecidea pa- 
rasema, vernalis, petrea, atro-alba, geographica, alpicola, sanguineo-atra, Friesiana, 
insignis. 
9. Absence of any fixed or constant anatomical distinction between spermogonia and 
pycnidia, spermatia and stylospores, sterigmata and basidia, e. y. in Peltigera canina, 
Nephroma arcticum, Lecidea cladoniaria, Lecanora subfusca. 
The organs known as thece and spores in Lichens being exactly what are called asci 
and sporidia in Fungi, it does not appear desirable to maintain different designations 
for the same organs in two groups so closely allied as Fungi and Lichens{. I have 
* Vide Pertusaria paradoxa, described under Lecanora oculata. 
+ Vide authors * History of British Lichens, pp. 326 & 341; and paper on “ Parasitic Micro-Lichens,” formerly 
quoted (p. 307). 
t Some Ascomycetes (says Berkeley in the * Treasury of Botany") approach Lichens so closely as to be searcely 
distinguishable, e. y. in their spermogonia and pyenidia. Fungi and Lichens are “so closely allied that it is often 
difficult to tell to which division some given species may belong." Hence he includes both under the common desig- 
nation * Fungals.” I have pointed out in various papers (e.g. * New-Zealand Lichens and Fungi," Trans. Royal 
Society of Edinb., vol. xxiv. p. 434) that there is a large group, provisionally termed “ Fungo-Lichens,” which have 
the characters equally of T" and Lichens, and which it is at present impossible to assign preferentially or exclu- 
sively to either family. — . 
