VAUCHERIA SESSILIS. 



THALLOPHYTES; ALG^; CHLOROPHYCE^. 



PRELIMINARY. 



THIS species of Vaucheria is quite common on the 

 damp earth and pots of greenhouses, and may often be 

 found out of doors in damp shady places. Other species 

 may also be found in similar places as well as in quiet 

 pools of water. The members of the genus may usually 

 be distinguished by their coarseness, the filament often 

 being large enough to be seen singly with the unaided 

 eye. When growing upon damp earth the slightly 

 brownish-green color and the felt-like appearance make 

 it rather easy to distinguish this plant from other Algae. 

 Material in the reproductive stage is not always found 

 easily in nature, and when found should be preserved. 

 It may be obtained by placing some of the vegetative 

 plants in a dish of water and putting them where they 

 will be well lighted. In this way zoospores and sexual 

 spores may usually be obtained in from five to ten days. 

 This treatment also produces new growth favorable for a 

 study of vegetative structures. 

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