1908.] 



TJie British Freshwater Phytoplankton. 



177 



species which occur in the different areas. As these records have never 

 previously heen correlated, we have drawn up the following tabulated list of 

 all the species observed in the phytoplankton of the British Islands. 



In this list those Algae, which, so far as is known, are exclusively confined 

 to the plankton are marked " P " ; those which are exclusively plankton- 

 varieties of species which frequently occur in other situations are marked 

 " Pv " ; and those species which are more abundant in the plankton than 

 elseivhere are marked " p." 



Species. 



X 



zz 



■J 





 02 



Orkneys and 

 Slietlands. 



W. and S.W. 

 Ireland, 



Welsh lakes. 



© 



a 



Lougli Neagli (and 

 L. Beg). 



Chloeophyce^:. 

















X 





X 



x 



X 



X 



„ punctato- striatum, De Bary 



X 















X 









X 

















X 



„ ,, var. variabilis (Kutz.), Kirchn 



X 



X 



X 



* 



X 





,, moniliformis, Kiitz 



X 



X 













X 





X 









Myxonema subsecundum (Kutz.), Hazen 







X 





















X 



M^icrospora amoena (Kutz.), Lagerh 



X 





X 



X 



X 





,, var. irregularis, W. and G*. S. West 







X 









, abbreviata Rabenli 











X 



X 





~&lov geotia s pp (sterile) 



x 



X 



x 





X 



X 



elegautitla W ittr 



x 









X 





1 Zygaema spp (sterile) . 



x 





7 



* 



X 





ericetorum (Kiitz ) Hansg 



x 













Sviroqvra spp. (sterile) 



X 





X 



X 



X 





Debarya glyptospenna (De Bary), Wittr 





X 













X 



X 



X 



X 



X 







x 





X 



X 



X 













X 







,, Kinahani (Arch.), Kabenh 



X 



X 



X 



X 







„ aculeatum, Hastings 



X 













Genicularia elegans, W. and Gr. S. West (P) 



X 















- 







X 







Mesotxnium macroeoccum (Kiitz.), Roy and Biss 







X 











X 













„ „ var. major, West 











X 





Netrium Digitus (Ehrenb.), Ifczigs. and Botlie 



7 



X 



X 



X 



X 







X 





x 









,, „ var. interruptum, W. and Cf. S. West... 









X 









X 





X 





x 





marqaritaceum (Ehrenb.), Breb., var. irregularius. 





x 1 











W. and Gr. S. West 

























X 









X 













X 









X 



X 



,, aciculare, T. West, var. subpronum, W. and 



X 





X 







i X 



a. S. West (p) 



















X 













X 





X 









