70 



hypnoides. Also Loiseleuria has branching year's-shoots and 

 no typical scale-leaves. 



From a vegetative point of view most of these Greenland 

 Ericineae agree very closely with Calluna, their chief means of 

 propagation being seeds; it is chiefly by the primary root that 

 the plant absorbs food from the soil, the adventitious roots 

 play a less prominent part in this respect. Decided deviations 

 from this rule are the Pirolas, Andromeda polifolia, Vaccinium 

 Myrtillus, Vaccinium Vitis-idœa and uligi?iosum, all of which 

 have subterranean runners with elongated internodes. It is 

 characteristic of the Ericineae that the adventitious roots spring 

 from the axils of leaves, above the buds. 



Of all the 16 species of Ericineae, mentioned above, two 

 only have typical deciduous leaves, viz. Vaccinium uliginosum 

 and Vaccinium Myrtillus. The leaves of Arctostaphylos alpina 

 appear neither to fall nor to keep fresh during winter. The 

 leaves of the other species keep fresh through at least one 

 winter, and the ensuing spring they appear to be able to assimilate 

 afresh; they are then found to contain starch; the leaves of 

 some of the species can evidently keep fresh even longer. 



The form of branching of the Ericineae is rather varied. 

 In the P«Vo/a- specie s a racemose inflorescence generally occurs 

 which terminates the growth of the pleiocyclic shoot; in this 

 genus the foliage-leaves occur in a few-leaved rosette. There 

 usually occur only subterranean lateral shoots which begin as 

 colourless runners bearing scale-leaves (see Warming, 1884). 

 Pirola uniflora is an exception (ibidem p. 86, Fig. 23). In some 

 of the Ericaceae the flowers occur singly in the axils of foliage- 

 leaves {Cassiope tetragona), or on small dwarf-shoots which 

 occur towards the base of the long-shoots, and bear only a 

 few pairs of foliage-leaves, dying after setting fruit (Calluna 

 vulgaris). Solitary flowers occur also in Vaccinium Myrtillus 

 (for further information regarding its sympodial growth, etc., 

 see Warming, 1884, pp. 76 — 77). Vaccinium uliginosum may 



