CBTPTONEMIAi 



al length surrounding the stem, Mart. Fl. Bra l. p. 27« 



(Atlas, PL XXIV. Fig. B 

 Tylocarpus Ghriffithfliffi, Kutz. T. tentaculatus (?), A' ■-.. I 



drus Gkiffithsi®, •/. A . Gigartina Ghriffithsise, Lamour. 



Polyidee Ghriffithsia?, Gaill. Sphamooccua Ghriffithsue, A . 



Erucus Ghiffithflifie, '/' 

 On Bubmarine rocks, near low-water murk. Perennial. 



Autumn and winter. 

 Though hitherto placed, in British works, in the genus 

 Gigartina, the Btructure of this plant is much more similar 

 to th&t of Chondrus. The structure, however, though similar, 

 is not identical; and as the tetrasporic fructification, which 

 alone is known to us, offers some peculiarities, J adopt th ■ 

 name invented by Von Martins for this and the □ 

 allied G. plicata. Tin* fructification is a most beautiful 

 microscopic object. The symmetry of the strings of tetra- 

 Bpores, each marked with a white cross, and each en 

 in its glossy pellicle, and brilliant as a ruby, is exqu 

 beautiful. The plant is dispersed on most of the A; 

 shores, from a high northern latitude to the tropics. It 



rally occurs within tide-marks. 



205. plioatus [The entangled Qymnogongrus); frond horny, cylin- 

 drical, filiform, very irregularly branched, entangled, wiry ; 

 branches Bub-dicbotomous ; axils obtuse; ramuli often Be- 

 cund ; fructification, oblong warts composed o\ obscurely- 

 jointed filaments, Kiz. 8p. Alg. p. 789. (Atlas, PLXLVI. 

 Kg. 211.) 

 Gigartina plicata, Lamour. Sphserococcua plicatus, Ag, Tylo- 

 carpus plicatus, Ktz. Fucus plicatus, 11 mis. s ■ . 

 hippuroides, Lyngb. 

 Hah. Ou rocks and Btones within tide-marks, and at a greater 

 depth. Perennial. Common. 

 There is a peculiar rigidity and wiriness in the frond of 

 this plant, which at once distinguishes it from any other 

 British Alga with which it can be confounded; and, when 

 dry. the glossy surface is equally striking. It often occurs 

 in Large bundles, \ >ry much tangled together, and then 

 looks like a mass of rigid dark-purple bristles. 1 have 

 never seen fruit perfectly ripe on any specimens that I 



examined. The wart-like receptacles of frail ar ■ 

 mon enough, but th >y seem to c >me to perfection b i 

 dom. This is very different from the habit of G. Griffith- 

 she, in whose g i \gri I is are always found, an 



some oi' the LUtiful of marine mic 



