THE MYXOPHYCE.E OF LAHORE. ll 



The Sub-family Schizotrickea is represented by Microcoleus 

 vaginatus Gam. (De Toni, p. 374 ; Cooke, p. 258, pi. 99, fig. 2, under 

 M. tcrrestris Deson) which lives commonly on damp mud, such as that 

 in lawns, flower-pots, and around ponds and ditches. Trichomes 

 long, collected in filiform, tortuous fascicles, enclosed in a common 

 mucous sheath, from the apes of which they come out in a penicillate 

 manner. Dissepiments granulated, Fascicles 75-80/* thick ; tricho- 

 mes 4-5/* thick. 



The family Nostocacecd is represented by Nostoc commune 

 Vauch. (De Toni, I. c. p. 404 ; Cooke, I. c. p. 231, pi. 91, figs. 4-7) and 

 Cylindrospermum majus Kuetz. The former is found in large abundance 

 in damp soil, even on lawns after a little rain or watering. Colonies 

 are at first globose and resemble Botrydium, then they expand and 

 become more or less irregular, but still keeping the outer membrane 

 intact. Trichomes flexuous, loosely intricate ; joints spherical, uni- 

 form about 5/* thick. Heterocysts globose, 7/* thick. 



Cylindrospermum majus Knetz. (De Toni, I. c. p. 424) is occasion- 

 ally met with, forming a bluish-green, thin expanded stratum on damp 

 mud. Trichomes 4-5/^ thick. Heterocysts oblong, 6-8/* thick. Spore 

 cylindrical, 10/* wide, 20-25/* long. 



From the Sub-family Scytonemacea, three species of Tolypothrix 

 are commonly met with in Lahore. Tolypothrix distorta Euetz. 

 (De Toni, p. 541 ; Cooke, p. 268, pi. 108, fig. 2) is very abundant in 

 stagnant or very slowly running water, such as the broad water- 

 courses of the Shalamar Gardens. It generally forms a very much 

 expanded bluish -green stratum on broad floating, half -decayed leaves, 

 such as those of the water lily. Trichomes and pseudo-branches 

 loosely interwoven, 8-11/* thick ; joints sometimes indistinct. Sheath 

 membranous, thin, sometimes inflated at the base of the branch, 

 hyaline, yellowish- brown when old. Heterocysts 8-9/* thick, and 

 12-14/* long. 



Tolypothriz byssoidea Kirchn. (De Toni, B.C. p. 551) forms a 

 dark brownish stratum on the trunks of trees such as those of Acacia 

 modesta, and is generally associated with Phormidlum ladmlanwm 

 and Phormidlum Hansglrgi. Trichomes 9-11/* thick, with irregular 

 pseudo-branches, torulose. Sheath thin, yellow or brown, fragile, 

 tubular. Heterocysts oblong, about 16/* long. 



Tolypothrix arenophila West (De Toni, I. c. p. 554) lives on damp 

 coarse mud, such as that in lawns or around ponds and ditches. At 

 first it forms small circular bluish-green, shiny patches, which expand 

 later on. By coalition of several such patches a very extensive 

 stratum is produced. Trichomos flexuous and contorted, densely 

 intricate, about 6/* thick, with few pseudo-branches. Sheath thick, 



