EUTETRAMORUS GLOBOSUS, A NEW GENUS AND 



SPECIES OF ALGJE BELONGING TO THE 



PROTOCOCCOIDEA (Family Coelastrida). 



L. B. Walton. 



While studying the plankton from "Mirror Lake," a small 

 pond on the campus of the State University at Columbus, Ohio, 

 exceedingly rich in phytoplankton at certain times of the year, 

 a form quite unique in structure was noted with much interest. 

 It consisted of 16 cells, each containing a chloroplast, the cells 

 being arranged in groups of fours and imbedded in an almost 

 invisible gelatinous matrix. The organism was non-motile with 

 no trace of flagella. The preparation was one taken from a 



Eutetramorus globosus n. g., n. sp. (x2000.) 



sterilized specimen bottle filled with water and floating alg^ — 

 mostly Cladophora — at the margin of the lake, Oct. 9, 1915, 

 the observation being recorded a few days later. An interval 

 of over two years has elapsed during which period various 

 samples of water from the lake have been studied without again 

 noting the species however. 



The organism is referable to the Family Coelastridce {Coelas- 

 tracea) of the Protococcoidea* and constitutes a new genus quite 

 different from forms thus far known. The drawing (Fig. I) 



*The endings of the Class and Family names are identical with those utilized 

 in a systematic review of the typically unicellular forms which will be published 

 shortly. They are an extension of those proposed by Poche (1911). Nomenclatural 

 methodology, particularly among the primitive plant-animal organisms is in a 

 somewhat chaotic condition. 



