THE AMERICAN 



MONTHLY 



MICROSCOPICAL JOURNAL. 



YOL. I. 



New York, January, 1880. 



m. 1. 



A New Species of Ophrydium. 



( OphrydiuTn-AdoB.) 



BY HERMANN C. EVART8, M.D. 



During the early part of the past 

 autumn, I found, in Taconj Creek, 

 Frankf ord, Philadelphia, large num- 

 bers of jelly-like masses, in most 

 cases, adhering to the under-sides of 

 smooth stones, sticks and leaves. 

 These masses were homogeneous, 

 transparent, colorless, nearly globu- 

 lar, and attached by a flattened sur- 

 face, in all instances adhering to 

 the stones or other articles, and 

 averaging from one-half to two lines 

 in diameter. In these apparently 

 lifeless jelly-masses, lived myriads 

 of infusoria. 



The masses were detached, with- 

 out injury, by means of a knife- 

 blade, and dropped into a jar con- 

 taining water, when they immediate- 

 ly sank to the bottom, and there 

 remained. They have not been 

 observed to attach themselves to 

 :any objects placed in the jar, nor 

 to the iar itself. 



So far as I can learn, only one 

 species of this genus .has been de- 

 scribed, viz. : Ophrydium versatile, 

 and that by Ehrenberg, who found 

 it in the sea in the form of gelatin- 

 ous masses, varying from the size 

 of a pea to that of a ball five inches 

 in diameter. 



"It has also been found, by 



Brightwell, in fresh water, and in a 



small turfy pit, on the tendrils of 



the roots of marsh plants and stalks 



, of the white water-lily." 



0. versatile is described as of a 

 vivid green color. When speci- 

 mens of the newly-found species 

 are first taken, they contain chloro- 

 phyll granules, but not in a suflfi- 

 cient number to give them a vivid 

 green color. When kept for some 

 time in the jar the chlorophyll 

 gradually disappears, unless they 

 have an abundance of food. 



When the colony is seen under a 

 low power, the foreign particles 

 floating about in the water are ob- 

 served to be moving rapidly from 

 all directions of the field toward a 

 common center, i. e., toward the 

 peristomes of the various individu- 

 als. 



After being transferred to the 

 stage of the microscope, they are 

 all seen to be contracted to a pyri- 

 form shape, probably from the dis- 

 turbance caused by moving them ; 

 but, if allowed to remain quiet for 

 a few moments, especially after the 

 water in which they are contained 

 has become slightly warmed by 

 standing in a warm room, they mani- 

 fest great activity, extending them- 

 selves, everting their peristomes, 

 and causing the cilia to move with 

 considerable rapidity, though not 

 with the same regularity of move- 

 ment that may be observed in most 

 of the Yorticellinse. 



As irritating particles float against 

 the cilia of the peristomes and discs, 

 the animals quickly contract. It is 

 highly interesting to observe some, 

 among the hundreds, slowly extend- 

 ing, while many others suddenly 



