NO. 2164. REVISION OF ROTATORIAN GENERA— EARRING. 559 



The width of the anterior margin is a little more than one-third 

 the length of the lorica. No dorsal sinus is present; the frontal edge 

 of the dorsal plate has a shallow median emargination between two 

 slightly convex lobes. The ventral sinus is V-shaped and pointed 

 posteriorly; its depth is one-fourth the length of the lorica. The 

 dorsal plate has a narrow stippled coUar, interrupted by a small 

 median triangular space; the ventral sinus has a comparatively wide, 

 thickened border of semielliptic outhne and with two rounded lateral 

 lobes. (See fig. 5.) 



The foot groove is rather short and wide, semieUiptic in outhne; 

 its length is but little more than one-fourth the length of the lorica 

 and its width four-fifths of the length. The posterior end of the 

 lorica is very slightly emarginate over the foot groove. 



The foot is fairly stout and somewhat more than one-third the 

 length of the body; the posterior joint is half the length of the entire 

 foot. The toes are one-fourth the length of the lorica and rather 

 slender, with shghtly recurved points. There is a sensory pit on the 

 dorsal side of the last foot joint. 



Total length, 180 m; length of lorica 118 /x, width 90 m; width of 

 anterior margin, 34 /z; depth of ventral sinus, 30 ix; length of foot 

 groove, 34 n, width, 27 /x; length of foot, 45 m, of last joint, 22 ju; 

 length of toes, 32 n; depth of body, 60 /x. 



This species was originally described by Rousselet from, notes and 

 sketches by Mi-s. PeU, of Highland Falls, New York. It seems to be 

 widely distributed in the eastern haK of the United States, and is 

 occasionally found in considerable numbers. Daday figures it from 

 African collections under the name Metopidia mucronata (Schmarda), 

 giving Lepadella mucronata Schmarda as synonym. As far as may 

 be judged from Schmarda's minute figure, his was an entirely different 

 form, with a high keel extending the entire length of the lorica and 

 continued beyond the posterior end of the body as a long spine. If 

 Schmarda's figure correctly represents the animal he found, it is 

 obviously very different from L. cristata. 



20. LEPADELLA RHOMBOIDULA (Bryce). 



Plate 96, figs. 1-4. 



Metopidia rhomboidula Bryce, Science Gossip, vol. 26, 1890, p. 76, text figs. — 

 Murray, Journ. Royal Micr. Soc, 1913, p. 459, pi. 19, fig. 7.— Montet, Rev. 

 Suisse Zool., vol. 23, 1915, p. 339. 



Lepadella rhomboidula Harring, Bull. 81 U. S. Nat. Mus., 1913, p. 65. 



The body is very broadly rhomboid in outline; its width is equal 

 to the length. The dorsal plate is slightly convex and has a high 

 median keel, extending the entire length of the lorica. The sides 



