Habits of Anthophysa Miilleri. 435 



both the larger and smaller cilium seems to be undergoing a 

 change^ and becomes indistinct in outline*. Presently two larger 

 flagella burst upon the view, apparently by the longitudinal 

 splitting of the previously single one of the same kind, and rapidly 

 separate from each other by the broadening of the body, and 

 leave between them the smaller cilium. The latter at this time 

 appears much thicker than usual, and seems to be composed of 

 two closely approximated parallel threads. By this time the 

 contractile vesicle has also divided into two, which lie closely side 

 by side. 



At this moment the time noted in one series of observations 

 was 2.30 P.M. By 3.35 p.m. the larger flagella had separated 

 still further, and the smaller cilium had split into two very con- 

 spicuous filaments, as yet, however, attached to a common point 

 of the body. From this time forth to the completion of the 

 process of fissigemmation all of the cilia kept up a slow vibra- 

 tion, in which they undulated from base to tip with a sort of 

 snake-like motion. By 2.45 p.m. the body had become quite ap- 

 preciably broader than long, the contractile vesicles were widely 

 separated, and the smaller cilia had left between them a consi- 

 derable space, and each one had approximated quite near to the 

 base of a larger flagellum. At 2.50 p.m. the body had become 

 nearly twice as broad as long, and the space between the two 

 pairs of cilia was nearly twice as great as in the last phase, and 

 considerably depressed in the middle, so that the body had a 

 broadly cordate outline. By 2.52 p.m. the posterior end of the 

 body (at a point a little to one side of the spot where it was 



* In a new freshwater genus (see note 2) of sedentary, monadiform 

 Protozoa (possessingtwo contractile vesicles, and only the sigmoid flagellum, 

 the latter arising within a deep bell-like flange or projecting rim which 

 embraces the anterior end of the body) this arcuate filament disappears 

 altogether, by a sort of withering down from tip to base, reminding one of 

 the shrivelling of the end of a cotton thread in the flame of a lamp, pre- 

 liminary to the commencement of the longitudinal fissigemiliation of the 

 body and its bell-hke flange ; and then the new flagellum of each resultant 

 of self-division grows out in about twenty minutes. 



2 Codosiga : /cwSwi', a bell, o-iydo), to be silent, C. pulcherrima, n. sp. 

 Body obliquely obovate, and tapering at its posterior end into a slender 

 pedicel ; truncate and abruptly constricted in front where the base of the 

 bell meets the body. Sigmoid arcuate flagellum as long as the body and 

 bell. The two contractile vesicles in the posterior third of the body; 

 superficial, large, and quite conspicuous, each contracting, alternately 

 with the other, once in about half a minute. Bodies attached, in groups 

 of from two to eight, by their pedicels to the tip of a slender stem j erect 

 or divergent, but not pendent. Mouth at the base of the flagellum, i. e. ter- 

 minal. Anus near the mouth. No eye-spot. Bell slightly flaring ; half 

 again deeper than broad ; fully as deep as the length of the body ; highly 

 contractile. Colour of the body (excepting the hyaline bell), pedicels, and 

 stem deep yellow. Common on fresh-water weeds about Cambridge, U. S. 



