188 MANUAL OF POISONOUS PLANTS 



by a gelatinous envelope, cell contents bluish green, brownish or reddish; 

 Merismopedia, with division in two directions, cells arranged in tabular groups 

 of 4, 8, 16, 32, 64, 128, etc.; Lyngbya, with filaments enclosed singly in a sheath, 

 branchless or occasionally branched, cell contents blue and granular. 



FLAGELLATAE 



One-celled organisms with nucleus, sharply differentiated protoplasmic body, 

 some with a simple membrane, pseudopodia absent, motile during most of their 

 existence; cilia 1 or more and with 1 or 2 pulsating vacuoles; chromatophores 

 occasionally absent; reproduction asexual by longitudinal division. The Eugle- 

 nalcs contain the family Euglenaceae. The most common of these is the Euglena 

 viridis which occurs in stagnant pools. Cells are elongated spindle-shaped, cilia 

 1 and with a red eye spot at one end. Water where these are abundant is not 

 wholesome. The Uroglena forms small sphaeroidal nearly colorless colonies, 

 the central portion of the colony is a hollow space filled with mucilage and the 

 ciliated cells are arranged around the periphery; vegetative multiplication occurs 

 by simple fission and by zoogonidia. The Uroglena, when occurring in large 

 quantities produce a fishy, oily odor. The related Synura produces an odor 

 of ripe cucumbers with a bitter and spicy taste. 



EUPHYCEAE 



Plants mostly occurring in water, always with a cell-membrane and nucleus. 

 Green or other colors mixed with the green (brown or red). This includes ah 

 of the algae or thallophytes that contain chlorphyll which is, however, fre- 

 quently masked because of other pigments like red and brown. 



PERIDINIALES 



Small 1-celled organisms of brown color, the chlorophyll masked by diatomin 

 found mostly in the plankton of salt water. 



BACILLARIALES 



Small 1-celled organisms of brown color, the chlorophyll masked by diatomin 

 of the chromatophores; cell-wall consisting of silica with a girdle and fine lines; 

 reproduction asexual parallel to the long axis of the organism and the forma- 

 tion of auxospores and sexual auxospores by conjugation. 



The diatoms are especially important in considering water supplies since 

 they are widely distributed and at times very common. The diatom is like a 

 pill box, made up of two parts, one fitting tightly within the other; the walls 

 are strongly silicified and marked with fine lines ; the cell contents are colored 

 brown. Economically, these algae are of some importance as food for fishes, 

 in manufacture of dynamite, and for polishing. 



Dr. Moore, speaking of Diatoms in water says : 



There are only a few species which are known to give rise to serious trouble in water 

 supplies, but these occur quite frequently and in great quantities. Sometimes the infected 

 water has an odor, variously described as resembling fish or geraniums, and the taste is 

 disagreeable enough to render it quite unfit for use. This condition is often produced by 

 Asterionella. In addition to this effect, however, diatoms are extremely troublesome when 

 contained in water to be used for the manufacture of paper or for laundry purposes, becausa 



