378 xxi. lyngbyejs (West). [Phorrnidium 
7. P. autumnale Gomont in Ann. Sci. Nat., I.e.. 187-190, t. 5, 
f. 23, 24 (1892). 
Oscillatoria autmnnalis Ag., /.c, 3G (1812). 
Forma tenuis W. et G. S. West, in Journ. Bot. 1897, p. 299. 
GOLUNGO Ar/ro.— Cum P. laminoso ad terram limosam postpluvias ; 
Dec. 1855. No. 166. 
4. PFvOTERENDOTHRIX W. et G. S. West in Journ Bot, 
1897, p. 299. 
1. P. scolecoidea W. et G. S. West, I.e. 
Huilla. — In Porphyrosiphone Notarisii, prope lac. Ivantala; March 
1860. Nos. 17 and 18.' 
This genus must be placed in the Lyngbyece on account of the 
structure of the sheath, which contains a solitary trichome. The com- 
parative width of the sheath, its hyaline character with irregular 
margin, along with the peculiar habit of the plant, characterise the 
genus. The younger plants (consisting of short filaments of 12-20 
cells) are endophytic, occurring between the lamellae of the sheath of 
Porphyrosiphon. As they increase in size they appear to break through 
the outer lamella? of the sheath of the host, and to attach themselves 
closely to its outer surface by means of their own mucous envelope, 
which is now r considerably broader. 
5. OSCILLATORIA Vauch. (1803). 
1. 0. limosa Ag. Dispos. Algar. Suec. 35 (1812) ; Gomont in 
Ann. Sci. Nat. 7 e serie, Bot. xvi. 610-2, t. 6, f. 13 (1892) ; W. et 
G. S. West in Journ. Bot. 1897, p. 300. 
Sierra Leone.— Ad terram et parietes juxta fontes prope Free- 
town ; Sept. 1853. No. 168- 
2. 0. tenuis Ag. Algar. Decas ii. 25 (1813) ; Gomont, I.e., 220 -1, 
t. 7, f. 2-3 (1892) ; W. et G. S. West, I.e. 
Ins. Principis. — In stagnantibus prope Bahia de S. Antonio, ad 
limum subexsiccantem late caespitosa ; Sept. 1853. No. 169. 
MosSAMEDES. — Cum Tolypotriche limbata in stagDis profundis prope 
Cavalheiros : Aug. 1859. No. 191. 
3. 0. animalis Ag. in Flora, x. 632 (1827) ; Gomont, I.e., 227-9 
t, 7, f. 13 (1892) ; W. et G S. West, I.e. 
Sierka Leone. — Cum Pkormidin Corium ad parietes humid, verticales 
urbis Freetown, freq. latissimis plagis atro-nitentibus parietes obducens; 
Sept. 1853. No. 167- 
4. 0. formosa Bory, Diet. Class. d'Hist, Nat, xii. 474 (1827) ; 
Gomont, I.e., 230-1, t. 7, f. 16 (1892) ; W. et G. S. West, I.e. 
Loanda. — In limo humido urbis Loandae ; April 1858. No. 170- 
5. 0. Okeni Ag. in Flora, x. 633-4 (1S27); Gomont, I.e., 232 
t, 7, f. 18 (1892) ; W. et G. S. West, I.e. 
Loanda. — In fonte tepida, sulphate (ferri '?) abundanti, pr. S. Pedro 
freq. ; July and Aug. 1854. No. 164. 
6. 0. angustissima W. et G. S. West in Journ. Bot, 1897, p. 300. 
Luanda. — Cum 0. Ohem in fonte tepida, sulphate (ferri?) abun- 
danti, pr. S. Pedro freq. ; July and Aug. 1854. No. 164. 
