On some new Forms of American Rotifera. 17 



III. — Some new Forms of American Rotifera, 

 By Dr. Alfred C. Stokes, 



[Plates VII. & Vm.] 



The following presumably undescribed Rotifera were all 

 taken from a shallow clear-water pool in a rocky wood near 

 Trenton, New Jersey, U.S.A. 



« 



Mastigocerca mucosa, sp. n. (PI. VII. fig. 1.) 



Lorica in dorsal aspect elongate-elliptical in outline; in 

 side-view obovate, about twice as long as broad (high), 

 ventral surface evenly and slightly convex ; dorsum arched, 

 higher anteriorly, and there bearing two anteriorly diverging 

 caringe^more than half as long as the lorica, the walls out- 

 wardly inclined, thickest at base, the furrow obliquely curved 

 toward the front, the bottom rounded ; anterior margin of 

 lorica truncate, smooth, the posterior aperture ventrally 

 oblique ; toe as long as the lorica, slightly decurved ; acces- 

 sory stylets four (or five?), the longest conspicuous, curved, 

 about one fourth as long as the slender, tapering, acute toe, 

 the three (or four?) additional stylets setiform and about one 

 half as long as the principal one ; antennaj clavate, appa- 

 rently not setigerous ; lateral antennas near the posterior 

 extremity, in close proximity to the ventral border, finely and 

 radiately setigerous ; brain elongate-saccate, with a large 

 papilliform purplish or black eye on its posterior extremity ; 

 alimentary canal large, broad, situated laterad and partly 

 ventrad to the ovary, which, in the writer's specimens, was 

 large, irregular in form, and with numerous developing germs ; 

 oesophagus long, conspicuous; contractile vesicle pulsating 

 about twenty-four times per minute ; flame-cells ('' vibratile 

 tags ") large. 



Length of lorica y^(j inch ; foot and toe tsit ; greatest 

 height of carina y^wo- 



Hah. As mentioned at the head of this paper. 



The secretion of the foot-glands is often so copious that it 

 seems to exude from the entire length and substance of the 

 toe, whence it spreads over the glass slide in waves and 

 filaments and fringes, and attaches the animal almost im- 

 movably, although it has the ability to withdraw the part 

 for a short distance from its colloid sheath, when the secretion 

 again exudes and again covers the toe as before. 



I have not been able to observe even a single seta on the 

 Ann. & Mag, N. Hist. Ser. 6- Vol. xviii. 2 



