THE MARINE BOTANIST. 213 



ters of spores. 2. Cruciate tetraspores immersed 

 in the outer surface of the frond. 



POLYIDES EOTUNDUS.— ROUND 

 POLYIDES. 



Fronds from four to six inches high, repeatedly 

 forked, with a rounded outhne, many stems spring- 

 ing from the same root. All the axils of the 

 branches rounded. In winter pale warts encircle 

 the upper branches, these of white articulate fila- 

 ments, among which are imbedded clusters of 

 spores (^favellce). The secondary fruit Mrs. Griffiths 

 has found in specimens from Sidmouth : these have 

 the upper ramuli slightly swollen, and contain im- 

 bedded tetraspores. This plant, when without 

 fruit, is known from the following by the rounded 

 axils of its branches and different root. Colour a 

 dark reddish-brown. Substance rigid when dry. 

 Grows on stones in sandy pools near low-water 

 mark. Perennial. Autumn and winter. Southern 



