370 ALGiE CONFERVOIDE.E. [Li/ngbt/a. 



annulated raid finally separating at the annuli into lenticular 

 sporidia. — A natural, but ill-defined genus, named by Agardh 

 in honour ot H. C.Lyngbye, an illustrious Danish Algologist, and 

 author of an excellent work on the Algce of Denmark. — 

 From Oscillatoria, its elongated flexile filaments will at once 

 distinguish it ; but it is more difficult to point out the line be- 

 tween Lyngbya and Calothrix ; though, in the typical species, the 

 habit be altogether unlike. 



* Terrestrial. 



1. L. murdlis, Ag. (Wall Lyngbya); filaments somewhat 

 rigid thickish tortuous interwoven into a bright grass-green 

 stratum. — Ag. Syst. Alg. p. 74. — Conferva muralis, Dillw. Conf. 

 t.7. E.Bot.t. 1554. — $. conjugata ; filaments united in pairs. 

 Carm. MSS. 



On damp walls, very common. — j8. near the sea-shore at Appin, Capt. 

 Carmichael. — Forming an intensely green stratum of indefinite extent ; 

 very conspicuous after a shower of rain. Striae strongly marked. 



** Growing in fresh-water. 



2. L. prolifica, Grev. ( prolific Lyngbya) ; " filaments ex- 

 ceedingly slender entangled purple very broadly effused floating." 

 Grev. Crypt. Fl. t. 303. 



In the loch of Haining, Selkirkshire, October to April. — " Plant 

 extensively diffused, forming a floating stratum of a rich purple colour. 

 Filaments extremely slender, entangled, somewhat rigid, yet flexible, en- 

 tirely destitute of attachment and free from any mucous layer. Annuli, 

 from the minuteness of the filament, almost inconspicuous." Grev. 



*** Marine. 



3. L. majuscula, Harv. (large Lyngbya); filaments very 

 thick, issuing in long crisped bundles from a blackish-green 

 stratum tortuous simple or slightly pseudo-branched. — Conferva 

 majuscula, Dillw. Conf Suppl. t. A. 



Santon sands, Miss Hill. Bantry bay, Miss Hutchins. Torbay, 

 Mrs. Griffiths. — Filaments forming blackish-green, interwoven strata, 

 from which they issue in crisped bundles, 1 — 2 inches long, very tor- 

 tuous, simple or occasionally agglutinated together, so as to appear 

 branched. Diameter greater than that of any of the genus, twice or 

 thrice as great as that of£. muralis. Endochrome dull-green, annuli 

 difficult to observe, close-set ; tube broad, hyaline. A fine species, that 

 Agardh erroneously refers to his L. crispa, which, according to an 

 authentic specimen, is a very different plant, of a verdigris-green colour 

 and thrice as slender. 



4. L. ferruginea, Ag. (rusty Lyngbya) ; filaments slender 

 flaccid forming a lax stratum of a verdigris-green colour, which 

 gradually changes to a pale chestnut. — L. ferruginea, (3. versi- 

 color, Ag. Syst. Alg. p. 73. — L. subsalsa, Carm. MSS. 



