370 xvi. sirosiphoniace.e (West). [Sliyonema 
4. S. informe Kiitz. Spec. Algar. 319 (1849); Tab. Phyc. ii. 
(1850-2), 11, t. 38, fig. iii. ; Born, et Flab., I.e., 75-77 (1887) ; W. 
•et G. S. West in Journ. Bot. 1897, p. 243. 
Pungo Andongo. — Inter Scytonema Myochrous var. chorographicum, 
in summis rupib. Prresidii (Pedras negras) ; Feb. 1857. No. 6. 
3. N0ST0CH0PSIS Wood (1869). 
1. N. lobatus Wood in Proc. Amer. Phil. Soc. Philadelphia, 127 
(1809); in Smithson. Contrib. Knowl. (1874), iii. 45, t. iii. f. G ; 
Born et Flab.., I.e., 80 (1887) ; W. et G. S. West in Journ. Bot, 
1897, p. 264. 
Goi.ungo Alto. — Ad rupes inundatas in rivulo Muria pr. Muria 
sparsius : Sept, 1854. No. 201. 
The examples of this are very fine, and agree well with the figure 
given by Wille (in Bihang t. K. Sv. Yet.-Akad. Handl. Bd. 8, no. 18, 
t. i. f. 1-19), with the exception of the cell-walls ; portions only were 
as moniliform as the previously-found African examples. (Cf. W. et 
G. S. West in Journ. Bot. 189(3, 381, t. 361, f. 1-2). 
The cell-walls are very thin indeed, not any more appreciable than 
the cell- walls in the ordinary vegetative cells of a Nostoc. The majority 
of the heterocysts are lateral, globose, and either sessile or stalked 
(usually supported on one or two cells) ; sometimes they are intercalary, 
and then they are always elliptic-oblong. 
XVII. SCYTONEMACEiE. 
1. SCYTONEMA Ag. (1824). 
1. S. cincinnatum Thur. in Ann. Sci. Nat. 6° serie, Bot. i. 380 
(1875) ; Born et Flab., I.e., 89 (1887). 
Calothrix lanata Kiitz. Algar. Aq. Dulc. Dec. I. no. 5 (1833). 
Var. aethiopicum W. et G. S. West in Journ. Bot, 1897, p. 264. 
Pungo Andongo. — Alga nigrescens, lubrica, tenax, rhizomata 
Xyridearum aliarumque plant, palustrium, in spongiosis crescentium, 
crassis membranis obducens, matricibus tenaciter adherens — sicque 
imprimis loca spongiosa formans. Cum DicJiotriche gypsophila et 
Mourjeotia irregular/ in pascuis spongiosis breviter graminosis juxta 
rupes gig. Prassidii prope Catete ; May 1857. No. 111. 
2. S. rivulare Borzi in Nuovo Giornale Bot. Ital. xi. 373(1879) 
Born, et Flab. I.e., 91 (1887); W. et G. S. West, I.e. 
Pungo Andongo. — Ad muscos rupestres rivulos crescentes perrepens, 
in Mimosarum sylvis pr. Pedras de Guinga ; Jan. 1857. No. 13. 
Stratum golden-brown or violet ; branches rather scarce, usually 
solitary, short, a little narrower than the primary filaments ; cells 
sometimes a little longer than the diameter ; sheaths constantly 
asperulate. 
This is a most interesting species, having been previously seen only 
from Italy by its original describer. 
3. S. Arcangelii Born, et Flab., I.e., 92 (1887) ; W. et G. S. 
West in Journ. Bot, 1897, p. 265. 
GOLTJNGO Alto.— Ad muscos prope fontem magn. ad Banza de 
Sobato de Bango sitam ; Sept. 1855. No. 159. 
