1925] SetcheUr-Gardner: Melanophyceae 409 



The species of Ectocarpws are numerous and often very puzzling;. 

 The principal accounts, thus far published for our coast, arc those 

 of Saunders (1898 and 1901 ) and that in our own report on the algae 

 of the northwestern coast (1903) as well as in our Phycological Con- 

 tributions VI (1922). We have subjected all of the material available 

 to us to careful scrutiny in the preparation of the following treatment 

 of our species. 



Key to the Species 



1. Chromatophores band-shaped 2 



I. Chromatophores discoid 20 



2. Fronds forming hemispherical tufts, growth apical or subapicaJ 



21. E. chantransioides (p. 430) 



2. Fronds not as above, growth chiefly intercalary 3 



3. Gametangia on both creeping and erect filaments 4 



3. Gametangia on erect filaments only (except E. confervoides f. variabilis) 5 



4. Erect filaments 8-10m diam S. E. Taoniae (p. 420) 



4. Erect filaments 12-25/x diam E. confervoides f. pygmaeus (p. 415) 



5. Fronds usually more than 1 cm. high 6 



5. Fronds less than 1 cm. high 14 



6. Fronds tightly twisted into branched, rope-like threads 



4. E. tomentosus (p. 417) 



6. Fronds more or less loosely tufted 7 



7. Fronds over 5 cm. high 8 



7. Fronds usually less than 5 cm. high 10 



8. Terminal ramuli short and acute 3. E. acutus (p. 415) 



8. Terminal ramuli long-attenuated 9 



9. Gametangia not terminating in hairs 2. E. confervoides (p. 412) 



9. Gametangia frequently terminating in hairs 13 



10. Gametangia usually over 100yu long E. confervoides f. parvus (p. 413) 



10. Gametangia usually less than 100/u long 11 



II. Fronds never corticated 12 



11. Fronds corticated 5. E. corticulatus (p. 418) 



12. Gametangia usually 50-70/z long 6. E. fructuosus (p. 419) 



12. Gametangia usually 75-90ju long E. confervoides f. variabilis (p. 414) 



13. Fronds loose, up to 20 cm. high 1. E. siliculosus (p. 410) 



13. Fronds tufted, up to 6 cm. high E. siliculosus f. subulatus (p. 411) 



14. Fronds penetrating the host more or less 15 



14. Fronds not penetrating the host 18 



15. Fronds more or less profusely branched 16 



15. Fronds mostly simple 17 



16. Gametangia long, attenuated 12. E. Mesogloiae (p. 423) 



16. Gametangia short, blunt 13. E. commensalis (p. 424) 



17. Fronds over 1 mm. high 14. E. eramosus (p. 424) 



17. Fronds less than 1 mm. high 17a 



17a. Erect filaments terminating in a hair 15. E. luteolus (p. 425) 



17a. Erect filaments not terminating in a hair 33. E. gonodioides (p. 439) 



18. Fronds attached by creeping filaments and by rbizoidal filaments 



from the lower cells 11. E. flagelliferus (p. 422) 



18. Fronds attached by creeping filaments only 19 



19. Fronds forming a velvety stratum 9. E. terminalis (p. 421) 



