io3o 
hy ils fewer chloroplasts, which are not so slraight, and by the proportionately larger 
zygospores. The latter are elliptic, witli somewhat pointed pôles, whereas Üiose of 
Sp. polgtaeniata are mu ch more rounded and not infrequently spherical. 
Other species of Spiroggra, allof which were slerile, were observed from Antioquia : 
n os 6 and 7; and Cundinamarca : n os i 4 , i 5 , 16, 19, 20 and 24. 
Family Desmidiaceæ. 
i4q- Gonatozygon monotænium De Bary. — Antioquia : n os 1 , 2 and 6. 
Var. pilosellum Nordsï. — Antioquia: n 0s 1 and 2. 
1 5 0. Gonatozygon pilosum Wolle. — Antioquia: n° 4. 
1 5 1 . Cylindrocystis Brébissonii Menegii. — Antioquia: n os r and 2. 
162. Netrium Digitus (Eiirenb.) Itzigs. and Rothe. (— Penium lamellosum Kütz. ; 
P. navigiam Turner; P. elegans Bernard). — Antioquia : n os 3 , 4 and 5 . Cundina- 
marca : n os 23 and 24. 
Var. constrictum W. and G. S. West. — Antioquia: n° 3. 
1 53 . Netrium Nâgelii (Bréb.) Lütkem. — Cundinamarca; n° 24. 
1 54 * Penium Cylindrus (Ehrenb.) Bréb. — Cundinamarca: n° 24. 
1 55 . Closterium abruptum W. West. — Cundinamarca : n° 24. 
1 56 . Closterium angustatum Kütz. — Antioquia: n° 3 . 
167. Closterium columbianum spec. nov. 
Cl. submediocre, cellulis diametro 6 ^g-plo longioribus, subrectis, leviter attenuatis 
polos versus, dorso leviter convexo, ventre recto, polis crassis et subtruncatis ; membrana 
lutea vel fuscescente, valde costata, costis visis 7, juxta apices punctata ; chromatophoris 
? 
Long. 208 y; lat. 33 y ; lat. apic. 18 p . (PI. XXIII, fig. 5 g). 
Antioquia : Laguna above Estrella near Medellin, Central-Andes ; altit. 2600 m. N° 4 - 
Only empty cells of tliis species were seen, in conséquence of which no statement can 
be made with regard to the nature of the chloroplasts. The general proportions of the 
cell, along with its straightness and the few strong costae, afford cliaraclers which are 
quite diagnostic. 
In general outline tliis species bears much resemblance to the Desmid described from 
Singapore as Cl. Legumen W. and G. S. West (in Journ. Linn. Soc. Bot. XXXIII, 
1897, p. 1 58 , t. 8, f. 5-7), but the latter has a thin and perfeelly smootli cell-wall. 
1 58 . Closterium didymotocum Corda. — Cundinamarca : n° 24 - 
159. Closterium excavatum Borge in Bih. till K. Sv. Yet.-Akad. Handl. Bd. 27, 
Afd. III, n° 10, p. 19, t. 2, f. 7-9. 
Long. 1 55 - 1 q 4 PC lat. 27-29 p.. 
Antioquia: n° 7. 
