ERRATA. 



Page 190, line 11 from the bottom, for '■'■ Chrysodomus antiquus" read 



"Bucciiium imdatum." 

 Page 201, bottom line, dele " South Africa " (cf. p. 334). 

 Page 250, line 13 from the bottom, dele " {see Appendix)." 

 Page 255, lines 3 and 6 from the bottom, for " Microcystina " read 



'■'■Microcystis." 



