•272 
ORGANOGRAPHY. 
BOOK I. 
rising from the thallus, and often resembling minute 
trees, as in Parmeiia glomulifera. Greville, 
17. Cyphellce^ are pale tubercle-like spots on the under surface 
of the thallus, as in Sticta. Grev. 
18. Lacunce, are small hollows or pits on the upper surface of 
the thallus. Grev. 
19. Nucleus proligerus^ is a distinct cartilaginous body, coming 
out entire from the apothecia, and containing the spo- 
rules. Grev. 
20. Lamina proligera, is a distinct body containing the spo- 
rules, separating from the apothecia, often very convex 
and variable in form, and mostly dissolving into a gela- 
tinous mass. Grev. 
21. Fihrillce^ are the roots. 
22. Excipulus^ is that part of the thallus which forms a rim 
and base to the shields. 
23. Nucleus, is the disk of the shield which contains the spo- 
rules and their cases. 
24. Asci, are tubes, in which the sporules are contained while 
in the nucleus. 
25. Thallodes, is an adjective used to express an origin from 
the thallus : thus, margo thallodes signifies a rim formed 
by the thallus, excipulus thallodes a cup formed by the 
thallus. 
26. Lorulum, is used by Acharius to express a filamentous 
branched thallus. 
27. Crusta, is a brittle crustaceous thallus. 
28. Gongyli, are the granules contained in the shields, and 
have been thought to be the spores by which Lichens 
are propagated : but this is doubted by Agardh. 
8. Algacece. 
These, with Fungi, constitute the lowest order of vege- 
table developement : they vary from mere microscopic ob- 
jects to a large size, and are composed of cellular tissue in 
various degrees of combination; some are even apparently 
animated, and thus form a link between the two great king- 
doms of organised matter. Their spores are either scattered 
