OF NORTHUMBERLAND AND DURHAM. 287 



30. POLYSIPHONIA, Grev. 



1. P. URCEOLATA, Grev. Harv. Man., p. 82. Phyc. Brit., t. 



167. Atlas, PL XXV., %. 109. Johnst. and 

 Cr., t. 11. 

 Conferva urceolata. E. Bot., t. 2365. 

 On rocks between tide marks, often covering them exten- 

 sively with, a brownish-red fleece; and on the larger Algse, espe- 

 cially on the stems of Laminaria digitata. Very common. Grow- 

 ing most luxuriantly near low-water mark, on such rocks as are 

 exposed to the full force of the waves. — N. D. 

 /3. PATENS, Harv. 



Chiefly on the stems of LaminaricB. A variety characterised 

 by its short articulations and short recurved ramuli. 



2. P. FORMOSA, Suhr. Harv. Man., p. 82. Phyc. Brit., 1. 168. 



Atlas, PI. XXV., fig. 110. Johnst. and Or., 

 t. 12. 

 On rocks between tide marks. Not common. At North 

 Sunderland and Whitley rocks. — G. S. B. In general appear- 

 ance not unlike the preceding species, but " much more -slender 

 and flaccid," and having much longer articulations in the main 

 stems. — N. 



3. P. FiBRATA, Harv. Harv. Man., p. 83. Phyc. Brit., t. 208. 



Atlas, PI. XXVL, fig. 113. Johnst. and Or., 

 t. 13. 

 On the sides of caves on the coast near Berwick, — Vr. G. 

 Johnston. At Holy Island. — Winch. — N. 



These habitats require further confirmation. It seems to me 

 very probable that the plant found by Dr. Johnston may be only 

 a byssoid variety of P. urceolata. 



4. P. ELONGATA, Grcv. Harv. Man., p. SQ. Phyc. Brit., t. 



292 and 293. Atlas, PL XXIV., figs. 105 and 

 106. Johnst. and Or., t. 15. 



