26 CONNECTICUT GEOL. AND NAT. HIST. SURVEY. [Bull. 



the Ulotrichaceae, but we follow West in placing - it here be- 

 cause of its yellowish-brown color. The plants are abundant 

 in all waters. 



T. bombycinum (Ag.) Derbes and Sol., Fig. 48. 



T. minus (Wille) Haz., Fig. 21. 



Chlorobotrys Bohlin. Plants are formed of solitary 

 globose cells, or of 2, 4, 8, or 16 cells associated in a family. 

 Each family has surrounding it an ample hyaline mucous tegu- 

 ment. The cell walls are thick and smooth. Six to thirty 

 parietal chromatophores are disposed on the wall of each cell. 

 Sometimes a red pigment spot appears in each cell. 



Multiplication by cell division, at first in two directions, 

 afterwards in three. 



Ophiocytium Nag. (inclus. Sciadium A. Br.). Cells 

 cylindrical, variously curved, attenuated at one end into a thin, 

 short stem ; sometimes both ends rounded, with or without a 

 spine. Propagation by non-motile spores or zoogonidia, which 

 are formed by division of the cell contents. The cell wall has 

 a lid fitted to the apex of a long tube. In the attached species 

 the zoogonidia come to rest on the rim of the empty cell and 

 develop into full-grown cells. A repetition of this process gives 

 a curious branched appeal ince. 



O. parvulum (Perty) A. Br., Fig. 20. The two different 

 sizes are, perhaps, two species. None of our specimens showed 

 the terminal spine. 



CLASS IV. CHLOROPHYCEyE. 



This class contains all the green Algae and numbers more 

 species than all the other classes of Algae together. The forms 

 are very diverse in size- and structure, and include unicellular, 

 filamentous, and colonial plants, some furnished with rhizoids, 

 others with hairs, and some with spines. Cell division usually 

 takes place in all the cells of a thallus, but occasionally there 

 is a growing point. Both sexual and asexual reproduction are 

 found in most of the families of the Chlorophyceae. This class 

 flourishes most abundantly in fresh water, though many are 

 marine, and members of it are to be found in every damp or wet 

 situation. 



