Ser. Melanospehme.e. Fam. Dictyotea. 



Plate VIII. 



PUNCTARIA LATIFOLIA, Grev. 



Gen. Chah. Frond undivided, membranaceous, flat, ribless, with a naked, 

 scutate root. Fructification scattered over the whole frond in minute 

 distinct dots, composed of roundish prominent seeds intermixed with 

 club-shaped filaments. Punctaria — from punctum, a dot\ the fruit 

 being in dots, scattered over the surface. 



Puxctahia latifolia ; frond oblong or obovate, suddenly tapering at the 

 base, pale olive green, thickish, gelatinous and tender. 



Puxctaria latifolia, Grev. Alg. Brit. p. 52. Hook. Br. FI. vol. ii. p. 278. 



Mack. II. Hih. vol. hi. p. 176. Harv. Man. p. 33. Wyatt. Alg. Damn. no. 9. 



J. Ag. Alg. Medit. p. 41 . Endl. 3rd Suppl. p. 25. Meneg. Alg. Hal. p. 174. 

 Phycolapathum debile, Kiitz. Bhjc. Gen. p. 292. t. 24. II. (in part). 



Hab. Kocks and stones in the sea. Annual. Summer. Sidmouth and 

 Torquay, Mrs. Griffiths, ^ear Belfast, Br. Brummond. Islay, Mr. 

 Chalmers. West of Ireland, frequent, IF. II. H. 



Geogr. Distr. British Islands. Mediterranean sea, in several places, J.Agardh. 

 Trieste, Herb. Hooker ! 



Desc Root, a flat naked disk. Fronds generally forming large tufts, 8-16 inches 

 long, 1-3 inches wide, oblong or lanceolate, flat or more or less curled or 

 wavy, generally obtuse at both extremities, occasionally tapering, when in 

 perfection delicately membranaceous, semitransparent and somewhat gela- 

 tinous, but becoming in advanced age thicker and coarser, always of a very 

 pale olive-green colour. Dots of fructification minute, roundish, thickly 

 scattered over both surfaces. It closely adheres to paper if gathered in an 

 early or middle stage of growth, but specimens collected later in the year 

 will not adhere to paper in drying. 



This species was founded in 1839 by Dr. Greville, in his ad- 

 mirable 'Algae Britannicae,' on specimens communicated by 

 Mrs. Griffiths and Dr. Drummond, and has since been detected 

 in tolerable plenty on several of our coasts. It is probable that 

 by earlier botanists it was confounded with P *. plantqpinea, to 

 which some of its varieties make a Dear approach in form, and 

 with which it is often found associated in the same pool. 1 have 

 specimens of both species gathered side by side by Mrs. Griffiths, 

 who observes, that " V.plantaginea is much thicker than P. lati- 



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