316 Marine Algce of Berwick -on-T weed. 



Rcematocelis Jissurata, but T have not had an opportunity of com- 

 paring them with authentic specimens of that species. In any 

 case my specimens agree well with the figure and description in 

 the "Florule du Finistere." 



The plant forms dark-red or purple crusts on stones and shells 

 near low-water mark. The fronds are from half an inch to an 

 inch and a half or even two inches in diameter, roundish or 

 irregular in outline, soft and gelatinous in substance, composed 

 of creeping threads from which arise vertical filaments bent 

 horizontally below. The articulations are three or four times as 

 long as broad below, much shorter above. The fruit of this 

 species is unknown. 



HiEMATOPHLiEA, J. Ag. 



H^MATOPHLyEA CROUANII, /. Ag. 



Descr. et Fig. Ha?matophla3a Crouanii, Crouan, Ann. Sc. Nat., 4th Ser., 



t. 9, pi. 3, fig. 6a-b-c ; Id., Flor. du Finist., pi. 19, fig. 125. 

 Syn. „ ,, J. O. Ag., Spec. Alg. n., p. 495 et 



Epicr? (eccl. Syn. Hilden. rubra Harv., Phyc. Brit.) 

 Sab. On rocks near low-water mark. Fruit Dec. — March. Berwick 



Bay. Very rare. 

 This rare and interesting species forms reddish, or blackish- 

 red, crusts on rocks and stones near low-water mark. To the 

 naked eye the crusts resemble those of Tlildenbrandtia rosea, but 

 under the microscope the difference between the two plants is 

 at once apparent. 



The fronds of Hcematophlaa Crouani are composed of large 

 nearly square cells, and the tetraspores, which are nearly as long 

 as the short paraphyses, are produced in superficial netnathecia, 

 as described by Crouan. The fronds of Hildenbrandtia rosea, on 

 the other hand, are composed of small cells, and the tetraspores 

 are produced in cavities sunk in the surface of the frond. 



In his Epicrisis Floridearuin,* Prof. J. G. Agardh expresses a 



* Epicrisis, p. 379. When speaking of H. Cronanii, Prof. Agardh says : — 

 " In specimine typico hujus plantas, mihi a eel. Crouan misso, paranemata 

 nulla vidi, ut in descriptione I.e. expressis verbis dixerira. Nostra, itaque, 

 species diversa videtur ab ilia, quain nomine H. Crouanii in Flor. Finist., 

 pi. 19, no. 125, pinxit celi, Crouan. Cum nostra, contra, convenie 

 videtur quae eodem loco sub nomine Hildenbrandtia: reject (PI. 19, fig. 12l5) 



