THE BEGINNINGS OF LIFE. 159 



dencies which may enable it ultimately to unfold into 

 one or other of the filamentous Algae 1 . 



On the other hand it must not be forgotten, that 

 however close the alliance may be between Fungi and. 

 Algae, the relationship is perhaps even closer between 

 Fungi and Lichens 2 . This is the opinion of the Rev. 

 M. J. Berkeley, who has included both under the com- 

 mon designation c Mycetales ;' and Professor Lindley 

 also said that Fungi and Lichens are c so closely allied 

 that it is often difficult to tell to which division some 

 given species may belong/ Dr. Lauder Lindsay, more- 

 over, states 3 that ( there is a large group, provision- 

 ally termed cc Fungo-Lichens," which have the cha- 

 racters equally of Fungi and Lichens, and which it is 

 at present impossible to assign preferentially or exclu- 

 sively to either family/ Some of the septate and 

 compound spores which I have found in ammonic 

 tartrate and sodic phosphate solutions are almost 

 precisely similar to some spores of West Greenland 

 Lichens which are depicted in Dr. Lindsay's very 

 interesting memoir 4 . But the relationship between 

 Algae and Lichens is just as close. According to Fries, 

 indeed, Lichens are types of Algals born in the air, 



1 The interchangeability of the two modes of growth will be sub- 

 stantiated by further evidence in subsequent chapters. 



2 -See Appendix D, p. Ixxvi. 



3 'Trans, of Linn. Soc.' vol. xxvii. (1871), p. 308. 



4 Compare also his Fig. 13-16 of PI. 51 with my Fig. d. of Appen- 

 dix A. 



