i8S3.] 



MICROSCOPICAL JOURNAL. 



205 



here referred to as J/. rol>iisfa^ w. sp., 

 is the largest yet recorded for any 

 member of the genus. For this rea- 

 son, and especially on account of the 

 impression conveyed by its substan- 

 tial appearance, robust seems an ap- 

 propriate specific title. 



M. robusta, n. sp. — Body ovoid, 

 varying to subspheroidal, attached to 

 the summit of a stout, rigid pedicel 

 four to five times its length ; collar 

 about one-half the body in height ; 

 flagellum occasionally terminating dis- 

 tally in a bulb-like enlargement ; con- 

 tractile vesicles two, placed posteriorly. 

 Body TjoVo inch in height. Solitary. 

 Haliitat. — Fresh-water, attached to 

 the rootlets of aquatic plants floating 

 in a tank where water-lilies were cul- 

 tivated. Its ability to alter its contour 

 is not great ; except to take a spherical 

 form, it has not been seen to change. 

 But one individual has come to my 

 notice with the flagellum bearing the 

 knob-like dilatation as represented in 

 fig- 37- ^t is probably a variety only, 

 as essentially the same organ- 

 ism occurs with the usual lash- 

 like appendage. This addition 

 to the flagellum appeared to 

 interfere in no way with its 

 movements, which however, 

 were not cjuite so rapid as in 

 the ordinary form, the bulb re- 

 maining indistinctly visible at 

 all times. The contractile ves- 

 icles pulsate alternately, each 

 at an interval of thirty seconds. 

 It may not be amiss to here 

 state that I have also taken a 

 single individual Trachelomo- 

 nas volvocina, Ehr., with the 

 flagellum distally bulbous. 

 \ — Whether the form was a local 

 variety remains to be deter- 

 mined. In this instance the 

 flagellum was voluntarily sep- 

 arated from the body, and the zooid 

 became apparently encysted within 

 the lorlca. Englcna viridis, Ehr., with 

 a bulb-bearing flagellum occurs in 

 English waters. 



M. IVoodicE, n. sp. (fig. 37/^.) Body 

 ovate, widest at the median line, taper- 



FiG. 37- 



MONOSir.A 

 ROBUST A. 



ing and sub-acute posteriorly, anteri- 

 orly somewhat constricted immediately 

 below the oiigin of the collar; length 

 one and one-half times the 

 width ; pedicel slender, 

 rigid, the length three to 

 four times thatof the body; 

 contrac^le vescicles two, 

 poste^iol^|y locatipd. Length 

 of the bo(V Ty;-;V(j\inch. Sol- 

 itary. Habitat! — Fresh 

 water, attached td^the root- 

 lets of thd same floating 

 plant with tne preceding. 

 It affordsWe pleasure to 

 Fig. 37*. dedicate thii graceful little 

 MoNosir.A creature to i\y friend Miss 



WOODI-U. T T\r 



Mary J. Woe 



M. longipjs^ n. sp. 

 Body glbbously ovati 

 length once and one-hr 

 to twice the breadth ; 

 icel slender, rigid, long, it^ 

 length six to seven times 

 that of the body ; collar ex- 

 ceeding the zooid in height.' 

 Length of the body a^do" 

 inch. Solitary. HalDitat. — 

 Fresh water, attached to 

 an alga growing in the Del- 

 aware and Raritan Canal. 



Remarkable for the great 

 length of the foot-stalk 

 when compared with that 

 of other species, and for the 

 height of the collar. A 

 favorite habit of the ani- 

 malcule seems to be the 

 protrusion of the body-sar- 

 code into short, tapering 

 processes extending as a 

 series circularly about the 

 zooid just below the begin- 

 ning or origin of the col- 

 lar. 



CODOSIGA. 



C. dichotonia, n. sp. — Bodies si 

 spheroidal or shortly ovate, station* ^ 

 sessilely to the extremities of a stout, 

 rigid, ciichotomously branching footJ 

 stalk composed of a main rachis two 

 or two and one-half times the length 

 of the body of a single zooid, attached 

 to the basis of support and furcately 



Fig 



MoNOSlC 

 LONGI I 



