168 ALG.E MELANOSPERME7E. [Fucus. 



linear-lanceolate, mostly proceeding from the terminal vesicles. 

 Grev. Hook. Br. Fl. v. ii. p. 265. E. Bot. t. 2131. 



On the western and southern shores. 



4. C. jibrosa, Ag. Fibrous Cystoseira. Frond bushy, very 

 much branched ; branches filiform, the terminating branchlets 

 (or leaves) nearly plane ; vesicles elliptical, mostly solitary ; 

 receptacles filiform, much elongated. Grev. Hook. Br. FL v. ii. 

 p. 266. E. Bot. t. 1969. 



On the western and southern shores. Galway Bay ; J. T. Mackay. 

 Bantry Bay; Miss Hutchins. Malbay ; W. H. Harvey. Black 

 rocks, Portrush ; Mr. D. Moore. 



2. HALIDRYS. Lyngb. Halidrys. 



Frond compressed, coriaceous, linear, pinnated with distichous 

 branches. Air-vessels lanceolate, stalked, divided by trans- 

 verse septa. Receptacles lanceolate, stalked, compressed. 

 Seeds in distinct cells. Grev. Name ; a\<?, aXts, the sea, and 

 />vs, an oak, or tree. 



1. H. siliguosa, Lyngb. Podded Halidrys. Vesicles com- 

 pressed, petiolated, linear-lanceolate, attenuated to a point. 

 Hook. Br. Fl. v. ii. p. 266. E. Bot. t. 474. 



Common on all our shores. The beautiful Fucus Osmundaceus, 

 Turn. 1. 105, from the North-west Coast of America, is a second spe- 

 cies of this genus. 



3. Fucus. Ag. Fucus. 



Frond plane, compressed or cylindrical, linear dichotomous, 

 coriaceous. Air-vessels (when present) innate in the frond, 

 simple. Receptacles terminal (except in F. nodosus], turgid, 

 containing tubercles imbedded in mucus, and discharging 

 their seeds by conspicuous pores. Grev. Name ; 0v/cos, a 

 sea-weed. 



1. F. vesiculosus, Linn. Bladdered Fucus. Frond coria- 

 ceous, flat, dichotomous, entire, furnished with a midrib ; vesi- 

 cles sphserical, (mostly in pairs) ; receptacles terminal, turgid, 

 elliptical. Hook. Br. Fl. v. ii. p. 267. E. Bot. t. 1066. 



Sea shores, very abundant. A very variable species ; many of the 

 varieties destitute of vesicles. Dr. Greville's variety " Caterjfructus" 

 is so completely intermediate with the following, that it may be de- 

 bated to which species it most properly belongs. 



2. F. ceranoides, Linn. Horned Fucus. Frond coriaceo- 

 membranaceous, entire, furnished with a midrib, pinnated with 

 lateral, dichotomous, fruit-bearing branches, without vesicles ; 

 receptacles lanceolate, linear, acuminated. Hook. Br. Fl. v, ii. 

 p. 267. E. Bot.t. 2115. 



