PH^EOPHYCE^E 119 



The unilocular sporangia occur (Pylaiella) in rows 

 of intercalary cells or (Isthmoplea, Ectocarpus, &c.) 

 as lateral outgrowths of the cells, generally sessile, 

 and oval or globular in form. 



The relationship of the order is undoubtedly a 

 close one with Sphacelariacece and other orders here 

 placed near it, but facts briefly alluded to above 

 compel one to look to orders like Tilopteridacece for 

 other marks of near alliance. 



The Geographical Distribution of this large order 

 is fairly general, but is most markedly abundant in 

 the North Atlantic though this probably means no 

 more than that it has been most studied here. Streb- 

 lonema, Edocarpus (many species), Isthmoplea, Pylai- 

 ella, Sorocarpus, Ascocydus occur in British seas. 



