Xerophytic Adaptations of Bryophytes. 183 
(8). Capillary Structures. 
A quick method of obtaining water is necessary when the supply 
is intermittent or limited, and any capillary apparatus will therefore 
assist a plant to maintain its local habitat. Many instances of 
capillary action have been alluded to already under the heads of 
other protective devices. It must be borne in mind that the 
presence of capillary apparatus does not show that the bryophyte 
is a xerophyte, as they are often found in plants growing in moist 
places, it simply indicates that the plant is capable of continuing 
its existence under drier conditions than if this method of obtaining 
water were absent and other conditions were similar. 
The following notes on the extremely varied forms of capillary 
apparatus give some of the chief points of interest in connection 
with this protective method. 
(«) Paraphyllia (Fig. 3, 24, 25). These small supplementary 
leaves are considered by Goebel to be stem-borne protonemal 
branches which have developed into cell-surfaces and cell-threads 
(7), and are also extra assimilatory organs since they contain 
chlorophyll. They are found chiefly in mesophytes and hydrophytes, 
though Thuidium recognition, T. Philiberti and the paraphyllose 
species of Hylocomium have fairly good claims to be considered 
semi-xerophytes, as they are often found on dry ground or rock. 
Other plants having these organs are Eurynchium prcelongum, 
Amblystegium filicinum, Hyocomium flagellare, Hypnum commutation, 
H. falcatum, and other species of Thuidium, besides those previously 
mentioned. In forms or varieties of these plants which grow in 
wetter places, the paraphyllia are often fewer or absent, as in 
Amblystegium filicinum var. Vallisclausce (=Cratoneuron Formianum) 
and H. falcatum v. virescens. 
Paraphyllia are also present on the calyptra of Trichocolea 
tomentella (14) and T. paraphyllia (7). 
(6) Tomentum on Stem. Rhizoids are generally present on the 
stem in creeping bryophytes, as in most liverworts and pleuro- 
carpous mosses, being sometimes especially abundant, as in Hypnum 
commutatum, Amblystegium filicinum, Lophozia alpestris, Gymno- 
mitrium crassifolium and in the wall form of Hypnum cuspidatum 
previously mentioned. Even in erect-stemmed acrocarpous mosses 
they are sometimes so abundant as to form a thick network, e.g., 
Polytrichum strictum, Bryum pseudotriquetrum, B. bimum, B. 
pallescens,A ulacomnium palustre, A noectangium compactum, Dicranum 
scoparium v. paludosum, D. undulatum, D. elongation, Fissidens 
