* 
738 THE AMERICAN NATURALIST. | [Vor. XXXV. 
gi. A bilobed glandular organ (Fig. 53, 4) attached close 
to the opening of the ovary and excretory organs ; 20-25 
flame cells on each excretory tube 
73, A. herrickii de Guerne (Fig. 53) 
£2. No glandular organ as described in 73; flame cells 
but 3-5 on each excretory tube 74, A. priodonta Gosse 
f2. Only one eye 
£I. Jaws stout, with doubly pointed ends not serrated 
(Fig. 54); flame cells 10-20 on each side 
75, A. brightwellii Gosse 
£2. Jaws weaker, ending in a blunt tooth and a broad, 
thin plate (Fig. 55) (probably a variety of the last) 
76, A. girodi de Guerne 
d». Very small rotifers, sac-like ; corona rising slightly to a 
single apex ; jaws not incudate ; not viviparous 
Ascomorpha 
er. A single large projecting process at the mid-dorsal edge 
of the corona 
ft. Ovate in form; hyaline except the stomach; on each 
side of the body a “sub-dorsal groove” . 77, 4. hyalina 
Kellicott (Fig. 56) 
fe. Flattened; in one view nearly circular, with a neck-like 
projection ; in the edge view oblong, half as long as wide; 
skin stiffened so as almost to form a lorica 
78, A. orbicularis Kellicott (?) 
(This species is probably founded on dead specimens of Gas- 
tropus stylifer, No. 153.) 
e2. No large projecting process on the corona ; dorsal view 
sac-like; lateral view unsymmetrical, with a gibbous dorsal 
outline ; color usually dark green . . . . 79,4. ecaudis 
Perty (A. helvetica Perty ; Sacculus viridis Gosse) (Fig. 57) 
à7. Foot not present; no appendages to body ; anus present 
cz. Parasitic in Volvox; having a large mid-dorsal projecting 
process on the corona . . . . 80, Hertwigia parasita Ehr. 
c2. Not parasitic ; body an elongated, parallel-sided, flattened sacó 
corona squarely transverse, with a single marginal wreath of cilia, 
and with two broad, flat setz-bearing prominences on the dorsal 
side and two long styles near the ventral side . 81, Anar thra 
aptera Hood (Fig. 58) 
(See also Trochosphera, No. = 
48. Foot present, ending in two toes placed side by side ; body with- 
out swimming appendages ; anus present 
cr. Form a broad, often swollen, cone, of which the foot forms the 
apex. Corona large, transverse, flat or strongly convex, with four 
