- 83 - 
Fig. 11. Umbilicaria Dillenii. Natural size A, 
view from above; B, diagrammatic vertical 
section, showing method of attachment to Fig, 12. Ramalina calicaris. Natural 
substrate. (Original.) size. (After Rabenhorst.) 
which subsequently gives rise to the spore-producing fruit. In such 
lichens as Parmelia, however, the most careful search has failed to 
discover any trace of a female organ, and there is other evidence that 
the spores arise in an entirely non-sexual manner. Moreover, the sper- 
matia of such lichens have been found 
to germinate and produce a mass of hy- 
phse entirely similar to that grown from 
spores. The conclusion seems warranted, 
therefore, that the spermatia of the major- 
ity of lichens have in the course of evolu- 
tion changed their function, and while 
they were orginally male reproductive bod- 
ies, they now serve as supplementary non- 
sexual spores. 
Having studied in detail one typical 
example, it remains for us to consider the 
principal modificatfons of form which the dif- 
ferent parts of lichens exhibit. 
The chief forms of thallus are briefly in- 
Fig. 13. Psnea barbata. Natural dicated in the Mowing table : 
size. (After Sachs.) 
I. Closely united with the substrate, so as to appear like an incrustation; without 
rhizoids. (Fig. 9) crustaceous 
II. Attached to the substrate by rhizoids or by definite portions of the lower surface; 
lobes numerous or ample foliaceous 
1. With numerous rhizoids or points of attachment. 
a. Lobes lying close to the substrate. (Fig. i) ADNATE or APPRESSED 
b. Lobes ample and ascendant. (Fig. 10) FRONDOSE 
2. With a single point of attachment near the center. (Fig. 11) UMBILICATE 
III. Arising from a single point of attachment and growing more or less perpendicular 
to the substrate; branched and shrubby or pendulous, the branches flattened. 
(Fig. 12) or terete (Fig. 13) FRUTICULOSE 
IV. Possessing both a horizontal and a vertical part, the former being crustaceous or 
foliaceous, and the latter consisting of individual members, called podetia , that may 
be goblet-shaped (Fig. 14, A), club-shaped, or cylindrical (Fig. 14, B), and either sim- 
ple or branched cladoni^eform 
