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IX. ALGA1. 
§ 2. Conceptacles scattered over the frond , or sunk in its joints, 
a. Frond with distinct stem and branches. 
Frond moniliform, interuodes inflated 10. Hormosira. 
Frond cylindric, proliferously branched 11. Splachnidium. 
Frond filiform, irregularly branched 12. Notheia. 
(8. Frond without stem and branches , flabellately expanded and 
palmately lobed 13. D’Urvill.ea. 
Tribe II. Sporochnoidese. Spores superficial, collected on proper branches of the 
frond (receptacles). 
Frond filiform, cylindric. Receptacles terminated by a pencil of 
filaments 14. Sporochnus. 
Frond filiform, compressed or flat. Receptacles conical or mitri- 
form 15. Carpomitra. 
Frond compressed or flat, linear ; branches pinnate, opposite . . 16. Desmakestia. 
Tribe HI. Laminariese. Spores superficial , forming cloudy sori of indefinite forms on 
the frond. 
Frond terete, slender, undivided, of immense length, bearing at the 
upper part a series of lanceolate leaves with a bladder at their 
base 17. Macrocystis. 
Frond with an erect, solid, dichotomous trunk, bearing branches 
and lanceolate leaves without bladders 18. Lessonia. 
Frond broad, pinnatifid, its stipes solid or hollow 19. Ec&lonia. 
• 
Tribe IV. Dictyotese. Spores superficial, forming dot-like or small sori of definite 
forms on the frond. 
Frond flat, dichotomous, flabellate, concentrically striated . . .20. Zonaria. 
Frond flat, dichotomous, linear 21. Dictyota. 
Frond cylindric, membranous, branched 22. Dictyosiphon. 
Frond saccate, membranous, unbrauched 23. Asperococcus. 
Series B. Frond not articulate, its outer stratum formed of radiating 
articulated filaments. 
Tribe V. Chordarieae. 
* Frond tubular or saccate, unbranched, filled with fluid. 
Frond cylindric, septate internally 24. Chorda. 
Frond saccate 25. Adenocystis. 
** Frond solid, cylindric, branched; axis of interlaced filaments ; periphery of 
radiating filaments immersed in gelatine. 
Axis of longitudinal filaments, radiating outwards to form the 
periphery 26. Scytothamnus. 
Axis cartilaginous, dense ; filaments of periphery unbranched . . 27. Chordaria. 
Axis gelatinous, loose ; filaments of periphery branched .... 28. Mesogeoia. 
*## F'rond solid, hemispherical or tuberous 29. Leathesia. 
Series C. Frond filiform, branched, of superimposed single cells, or of 
longitudinal series of cells of equal length, hence articulate. 
Tribe VI. Ectocarpese. 
Articulations of 3 or more parallel cells 30. Sphacelaria. 
Articulations of solitary cells - 31. Ectocarpus. 
