t o 1 9 — 
Tamily T(ivulariaceæ. 
35 . Calothrix parietina (Næg.) Thuret. — - Cundinamarca : n os r 4 , 17 and 20. 
Crass. fil. 1 5 - 1 8 (usque ad 24) y- ; crass. trich. 9-12 y.. 
36 . Calothrix brevissima G. S. West in Journ. Linn. Soc. Bot. XXXVIII, 1907, 
p. 180, t. 10, I'. 8. 
Forma trichomatibus paullo latioribus ; crass. fil. 6 - 8,5 y. ; crass. trich. 4 , 5 - 7 , 5 p. ; 
long. tôt. trich. 36-42 y.. (PI. XXI, fig. 8-9). 
Cundinamarca : n° i 4 . 
67. Calothrix columbiana sp. noy. 
C. parva, fi lis gregariis, ad plantas varias submersas affixis, usque 35 o y. longis, 
subrectis vel leviler fïexuosis, ad basin sæpe decumbentibus, apicem versus gradatim atte- 
nuatis ; vagina arcta achroa et submucosa, non lamellosa ; trichomatibus pallide ærugi- 
neis, inter cellulas non constrictis ; cellulis basin versus subquadratis vel dia métro paullo 
ongioribus, cellulis apicem versus subcylindricis, diamelro circiter 3 -plo longioribus ; 
heterocystis solitariis, basilaribus et subsphæricis ; sporis solilariis ellipsoideis, polo juxta 
cellulas vegetativas subtruncato et incrassato, episporio glabro et achroo. 
Crass. trich. ad bas. 6-8 y, ad med. circiter 4-5 y . ; diam. heterocyst. 6 y., long. spor. 
1 2- 1 4-> 5 y. ; lat. spor. 10 y.. (PI. XXI, fig. 10-12). 
Cundinamarca : Laguna de Ubaque, Eastern Andes ; altit. 2066 m. N° 23 . 
This species is a close ally of C. stagnalis Gomont (in Journ. de Botanique, 1895, 
p. 197, cum fig.), but differs in ils shorter filaments, its solitary heterocysts, its cylin- 
drical cells with entire absence of intercellular constrictions, and in its shorter and diffe- 
rently shaped spores. 
38 . Calothrix sp. ad C. stagnalem accedens. 
Crass. trich. ad bas. 6,8-8 y. ; diam. heterocyst. 6,5-7 [x. Cundinamarca : n° i 4 - 
Very little of this species was seen. It is epiphytic on various aquatic macrophytes. 
From C. stagnalis it differs in its solitary heterocysts and (in the few specimens obser- 
ved) in the absence of spores. 
3 q. Calothrix clavata sp» nov. 
C. minuta, filis solitariis vel subgregariis, ad plantas submersas epiphy ticis, usque 
100 y . longis, subrectis vel leviter (lexuosis, ad basin inllatis, supra basin subiter attenua- 
tis et deinde gradatim attenuatis apicem versus ; vagina arcta, achroa et tenuissima ; 
trichomatibus pallide ærugineis, inter cellulas latiores basales leviter constrictis ; cellulis 
ad basin brevibus et discoideis, in parte superiori cylindricis cum diametro 2-3-plo longio- 
ribus ; heterocystis solitariis, basilaribus et hemisphæricis. 
Crass. fil. ad bas. 7 y. ; crass. trich. ad bas. 5 - 5,5 <x ; crass. trich. ad med. 2,5 y.. 
(PI. XXI, fig. 6-7). 
