144 YORKSHIRE NATURALISTS* UNION. 



714. Schizothrix calcicola (Ag., 1812) Gomont. 



Mid W. — Amongst Scytoneina sp., on wet rocks, Linn Gill. 

 This species has not previously been recorded for the British 

 Isles. 



Family Z YNGB YE^. 



Sub-Family LvNGBYOiDEyE. 



Genus PLECTONEMA Thur., 1875. 



715. Plectonema Tomasinianum (Kiitz., 1836) 

 Bornet, 1889. [Syn. Calothrix Tomasinianion Kiitz., 

 1843; Plectonema mirabile Thur., 1875]. 



Mid VV. — Ingleton. Malham. Forming expanded greenish- 

 brown tufts on wet rocks, Simon's Fell (iv.,1892). Thickness, fila- 

 ments, 16 — 19 fi; thickness, trichome, i2'5 — 15 j^j^. 



At or near the base of a few of the branches peculiar rounded 

 cells of a yellowish colour and with thick walls were occasionally 

 noticed; these are most probably spores. 



N.W. — Snaizeholme Beck. Widdale Beck. 



N.E. — Rievaulx Abbey. 



Genus SYMPLOCA Kiitz., 1843. 



716. Symploca muralis Kiitz., 1843. 



S.W. — On damp ground, Frizinghall. Thickness, trichome, 



37— 4"5^- 



Genus LYNGBYA Ag., 1824. 



717. Lyngbya Martensiana Menegh., 1837. [Syn. 

 Oscillatoria turfosa Carm., 1841; Lyngbya turfosa 

 (Carm.) Cooke, 1884]. 



S.W. — Doncaster. 



Mid W.— Linn Gill. 



N.W. — Vertical face of dripping rocks. Hell Gill Beck. 



In 1888 we recorded Lyngbya turfosa from Doncaster. Since 

 then M. Gomont's Monograph of this group has been issued 

 (1893) and in it we find Oscillatoria turfosa in a list of ^^ Species 

 inquirendcR.'" We have re-examined this plant and find that it 

 corresponds exactly with Cooke's figure (Brit. Freshw. Alg., pi. 

 102, f. 3) of Lyngbya turfosa which he states (I.e. p. 261) to be 



Trans. Y.N.U., 1899 (pub. July 1901). Bot. Series, Vol. 5. 



