Distrihutioyi of the Laminariacece. 351 



2. Saccorhiza, DelaPyl. — Frond possessing a distinct blade and 



stipe. Paraphyses destitute of hyaline appendages at the tip. 

 Sori not covering the whole surface. 



3. Laminaria, Lam'x. — Frond possessing a distinct blade and stipe. 



Paraphyses provided with hyaline appendages at the tips. Sori 

 not covering the whole surface. 

 Subtribe 2. Agareae. — Fronds provided either with ribs, or with 

 scroll-like auricles at the base of the blade, or with both. 



4. Cymathcere, J. Ag. — Blade provided with three (or five ?) ribs 



(or plicae ?) and destitute of perforations, bullate swellings, or 

 auricles at the base; bilateral. 



5. Gostaria, Grev.— Blade provided with five ribs and bullate swell- 



ings which occasionally form perforations, but destitute of auri- 

 cles at the base; bilateral. 



6. Agarum^ (Bory), P.&R. — Blade provided with a midrib, with 



perforations, and with auricles at the base; bilateral. 

 Y. Thalassiophyllum^ P.&R. — Blade unilateral, provided with per- 

 forations and a scroll-like transition-place but destitute of a 

 midrib. Frond irregularly branched by proliferation from the 

 margins of the perforations. 



8. Afthrotliamfinus^ Rupr. — Blade bilateral, plane, with auricles at 



the heart-shaped base. Stipe dichotomous provided with a 



spiral scar, erect or decumbent. 

 Tribe II. Lessoniide^. — Frond compound. New blades arising 



from the old by a splitting process at the transition-place. 

 Subtribe 1. Lessoneae. — Stipe dichotomous. 



A. Stipes solid. 



9. Dictyoneuron^ Rupr. — Divisions few ; stipe creeping and root- 



ing ; blades reticulately veined. 



10. Lessonia, Bory. — Divisions numerous ; stipe erect, blades plane 



or wrinkled, sometimes provided with a midrib. 



B. Stipes hollow. 



11. Fostelsia^ Rupr. — Stipe cylindrical throughout. 



12. N^ereocystis^ P.&R. — Stipe expanded at the apex into a large 

 bladder. 



Subtribe 2. Macroeysteae. — Stipe sympodial. Branching irregular. 



13. Macrocystis, Ag. 



Tribe III. ALARiiDKyE. — Frond pinnately compound. Sporophylls 



arising as outgrowths at the transition-place. 

 Subtribe 1. Eekloneae. — Sporophylls situated upon the blade. 



14. Ulopteryx Kjellm. — Blade provided with a distinct midrib and 

 with cryptostomata. 



