•J(U) .ions. iJOTi: i>i ri;nsi:N 



(»r tlu' vasl (li'sert and also lo a ^rrat i'xlnil iii llu' souIIutii regions 

 M) inaciH'ssil)K\ praclically iio alj^au have berii collecled. 



l-'or every specirs tlu' arca is riirlhcrmorc i^iven i. e. ils dislri- 

 bulioii over llie worid as far as il is kiiown al llie |)resent iiioinent. 

 These statements aie based: — 1) oii llie iiiiormatioii oblaincd Ironi 

 De-Toni: Sylloj^e Algaruni ; 2) on tbe alj^oloj^ieal literalure al niy 

 disposal Ironi tbe time alter tbe (inisbing ol" tbis work (H)07). On 

 perusal ol tbis extensive literalure I have at tbe same time noted 

 what tbe autbors bave remarUed in respecl lo tbe babitat ol" tbe 

 individual species. I bave endeavoured lo luse all tbese items wilb 

 Ihe information contained in I)e-Toni (A. Forti) and in tbe mono- 

 grapbies, and il is inciuded among tbe remarks on tbe individual 

 species. 



