No. 417.] MWORTH-AMERICAN INVERTEBRATES. 757 
above ; ventral plate excavate behind for the foot; eyes 
two . 232, M. lepadella Ehr. (Fig. 164) 
Fa. Similar to d fat but with four eyes. (Perhaps only a 
variation of the last) . . 233, M. bractea Ehr. 
J4. Lorica elliptical or ord nae: toes long, slender ; 
,eyes two or four ; foot of three nearly equal joints 
234, M. oblonga Ehr. (Fig. 165) 
J5. Like the last (of which it is probably only a variation), 
but with the third joint of the foot equal in length to the 
other two together ; the two toes protruded between two 
minute lateral spines . 235, M. dentata Turner (Fig. 166) 
fo. As in M. oblonga, but with the anterior margin of the 
lorica covered with points, so as to form a stippled collar ; 
the angles of the lorica at the sides of the head very sharp, 
so as almost to form spines (variation of M. oblonga ?) 
» M. collaris Stokes (Fig. 167) 
e2. Lorica rhomboid-ovate in outline ; dorsal plate roof-shaped, 
lower behind and ending in an obtuse point ; ventral surface 
237, M. rhomboides Gosse 
£3. Loca siis viding bekindi in an acute point 
238, M. acuminata Ehr. 
e4. Lorica with three wide, thin wings, one dorsal and two 
lateral ; the dorsal view nearly circular 
239, M. triptera Ehr. 
e5. Lorica broad behind, having four prominent angles, two 
lateral and two posterior 
240, M. ehrenbergii Perty (Fig. 168) 
e6. Lorica with two great spines at the anterior dorsal margin ; 
these separated by a narrow median notch 
241, M. cornuta Schmarda (Fig. 169) 
ANN ARBOR, MicH., Feb. 5, 1901. 
SOME OF THE MORE IMPORTANT LITERATURE ON THE 
ROTATORIA. 
I. Most IMPORTANT GENERAL SYSTEMATIC WORKS. 
EHRENBERG, C. G. Die Infusionsthierchen als vollkommene Organismen. 
Leipzig. 1838. (Still one of the most important works.) 
N, C. T., and Gosse, P. H. The Rotifera, or Wheel Animalcules. 
2 vols., with supplement. London, Longmans, Green & Co. 1889. 
(Indispensable. ) 
Hupsox 
