154 TiUlni — Notes on a Collection of Algse from Guatemala. 



Phormidium valderianum. 



Phormidium valderianum (Delp.). Gomont, Monogr. des Oscill. in Ann. 



Sci. Nat. Bot. VII, 10: 167. pi. 4. f. 20. 1892. 



Stratum slimy, expanded, lamellose, 8 mm. thick, the upper layers 

 dull green, the internal layers whitish; trichomea aeruginous, straight, 

 not attenuate at apex, not constricted at joints, 2-2.5 mic. in diameter; 

 cells somewhat longer than the diameter, 3.3-6. 7 mic. long; apical cell 

 rotund ; calyptra none. Associated with Nodularia harveyana. Laguna, 

 Lake Amatitlan. Altitude 3,950 feet. W. A. Kellerman (no. 4304), 

 February 8, 1905. 



Phormidium laminosum. 



Phormidium laminosum (Ag. ) Gomont, in Journ. de Bot. 4:355. 1890. 



Stratum forming a dark-colored or reddish, firm crust; plants flexuose, 

 densely intermingled; sheath narrow, more or less distinct; trichomes 

 pale bluish-green, not constricted at the joints, with straight, briefly 

 attenuated, non-capitate apex, 1-1.5 mic. in diameter; cross walls not 

 visible. Near Lake Amatitlan. In a pool of very warm water close to a 

 hot spring. W. A. Kellerman (no. 505)!), January 25, 1906. 



Phormidium uncinatum. 



Phormidium uncinatum (Ag. ) Gomont, in Journ. de Bot. 4:355. 1890. 



Stratum widely expanded; plants straight or somewhat flexuous; sheatli 

 not distinct; trichomes aeruginous, not constricted at the joints, 6-9 mic. 

 in diameter, briefly attenuated at the apex, capitate, curved or briefly 

 spiral; cells 2-3 times shorter than the diameter, 2-6 mic. long; cross 

 walls frequently lined with granules; apical cell having a rotund calyptra. 

 Lake Amatitlan. On rocks at the edge of lake and also on dry rocks, 

 same locality. W. A. Kellerman (nos. 501))! and 5067), January 28, 1906. 



Lyngbya martensiana. 



Lyngbya martensiana Menegh., Conspectus Algol, euganese. 12. 1837. 



Plants elongate, somewhat flexuous, flexible; sheath hyaline; trichomes 

 pale blue-green (violet in dried material), not constricted at the joints, 

 with non-attenuate apex, li-10 mic. thick; cells shorter than the diameter, 

 1.7-3.3 mic. long; cross walls visible; apical cell rotund; calyptra none. 

 On stems of Scirpus, dead or dying. Lake Amatitlan. W. A. Kellerman 

 (no. 5001), January 28, 1900. 



Lyngbya Iagerheimii. 



Lyngbya Iagerheimii (Moeb. ) Gomont, Journ. de Bot. 4:354. 1890. 



Plants more or less regularly spiral or straight; sheath thin, hyaline; 

 trichomes about 2 mic. in diameter; cells shorter or longer than the 

 diameter, 1.2-3 mic. long; cross walls marked by two refringent granules 

 (not visible in the preserved specimens). < >n stems and on lower branches 

 of a tree which had been cut oil' and thrown into water. Lake Amatitlan. 

 W. A. Kellerman (no. 5068), January 30, 1900. 



