PLOCAMIUM VULGARE, OR COCCINEUM. 195 



of a rich crimson with a pellucid border, and, seated in their 

 little cage of crimson pinnulse, are really beautiful. 



Another kind of fructification is found on Ptilotse, but 

 on distinct individuals ; the pinnulse are broader at the tips, 

 and covered with oval bodies called tetraspores, from their 

 containing/owr seeds. 



Ptilota is a perennial plant found in Summer and Autumn 

 frequently growing on the stems of Lammaria digitata, and 

 therefore our best specimens may be gathered on the beach 

 after the autumnal equinoctial gales. At Torquay it is 

 found on rocks, but Ptilota sericea is often mistaken for it ; 

 this is very abundant on the rocks at Moulin Huet in 

 Guernsey, hanging in rich silky masses on the sheltered 

 side of the rocks, and thronged with that minute but lovely 

 zoophyte Eucratia chelata. 



PLOCLAMIUM VTJLGARE, OR COCCINEUM. 



Plocamium, coccineum it is called from its fine crim- 

 son colour, and the word Plocamium means, in Greek, 

 "braided hair," which the fine divisions of the frond 

 resemble. 



A small branch of this lovely weed has been thus hap- 

 pily described in a French botanical work, and will direct 

 the eye in examining this slide. I shall therefore tran- 

 scribe it : 



" Sa tige est tres-rameuse, et toujours dans le meme 

 plan ; Fordre des ramifications est tres-remarkable ; chaque 

 rameau est legerement flexueux, et n'emet de ramifications 

 que du cote convexe : la premiere est un filet simple et 

 pointu ; la dewieme est un filet qui a trois dents du cote 

 anterieur ; la troisieme est un filet qui a deux dents, et qui 

 au lieu de la troisieme dent pousse un filet muni d'une dent 

 en dehors ; la quatrieme est un filet qui n'a qu'une dent, la 

 deuxieme dent est devenue une filet a une dent, et la 

 troisieme un filet rameux. 



c { Apres ces quatre ramifications il y a une espace vide, 

 <et la tige emet des rameux semblables du cote oppose/' 



The fructification is of two kinds : 



