THE BEGINNINGS OF LIFE. 159 



dencies which may enable it ultimately to unfold into 

 one or other of the filamentous Algse^. 



On the other hand it must not be forgotten, that 

 however close the alliance may be between Fungi and 

 Alg^5 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 ^Mycetales;' and Professor Lindley 

 also said that Fungi and Lichens are 'so closely allied 

 that it is often difficult to tell to which division some 

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

 over, states-^ that ^ there is a large group, provision- 

 ally termed " 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^. But the relationship between 

 Algse 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. 



- See Appendix D, p. Ixxvi. 



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



* Compare also his Fig. 13-16 of PL 51 with my Fig. d. of Appen- 

 dix A. 



