Marine Algce of Berivick-on-Tweed. 245 



considers Harvey's description and figure represent a different 

 and distinct species which he has accordingly called Calotlirix 

 Harveyi. Bornet and Flahault regard Calotlirix fasciculata as a 

 good species, distinguished from Calotlirix acopulorum by the 

 fascicles of pseudo-branches attached a little above the middle 

 of the filaments, and the numerous intercalary heterocysts. 



MIOROCH^TE, Thuret. 



MlCROCH^ETE GRISEA, TllUfet, 



Essai de Classific. des Nostoch., pp. 4 et 7. 



Descr. Microchaote grisea, Thuret, I.e. 



Fig. „ „ Bornet et Tliur., Notes Algol., pi. xxx. 



Syn. „ ,, Bornet et Flahault, Rev. Nost. Heteroeyst. 



I.e. vol. v., p. 85. 



Hah. On an old shell mixed with Calotlirix Crustacea. Berwick Bay. 



This minute species forms greyish patches on old shells. It 

 closely resembles a small species of Calothrix, but the filaments 

 end in a rounded cell not in a hyaline hair as in the genus 

 Calothrix. 



MASTIGOCOLEUS, Lag. 



Mastigocoleus testarum, Lagerheim, 



In Notarisia, 1886, no. 2, p. 65, tab. 1. 

 A very curious and interesting plant which belongs to the 

 class of perforating Algse which grow within the chalky shells 

 of dead or living molluscs. The present species forms bluish- 

 grey or violet stains, which at first are roundish but afterwards 

 become irregular in outline, on old shells. It is described and 

 figured by M. Lagerheim in Notarisia. 



