NO. 2164. REVISION OF ROTATOR! AN GENERA— EARRING. 563 



1. LOPHOCHARIS SALPINA (Ehrenberg). 



Plate 97, figs. 1-5. 



Lepadella salpina Ehrenberg, Abh. Akad. Wiss., Berlin (for 1833), 1834, p. 209; 

 Infusionsth., 1838, p. 458, pi. 57, fig. 3.—? Tessin, Arch. Naturg. Mecklen- 

 burg, vol. 43, 1890, p. 162. 



Metopidia salpina Hudson and Gosse, Rotifera, Suppl., 1889, p. 46. pi. 34, 

 fig. 4.—? Jennings, Bull. U. S. Fish Comm., vol. 19 (for 1899), 1900, p. 95.— 

 Diepfenbach, Siisswasserfauna Deutschlands, pt. 14, 1912, p. 189, text fig. 



Metopidia oxysternum ? Glasscott, Sci. Proc. Royal Dublin Soc, n. ser., vol. 8, 

 1893, p. 75. — Bilfinger, Jahresh. Ver. Naturk. Wiirttemberg, vol. 50, 1894, 

 p. 59.— Weber, Rev. Suisse Zool., vol. 5, 1898, p. 637; pi. 23, figs. 1-5. 



Oocysterna major Iroso, Mon. Zool. Italiano, vol. 21, 1910, p. 304. 



Metopidia oxysterna Diefpenbach, Siisswasserfauna Deutschlands, pt. 14, 1912, 

 p. 187, text fig. 



Lophocharis oxysternum Iroso, Atti R. Ist. Incorr. Napoli, vol. 64 (for 1912), 

 1913, p. 477, fig. 8. 



The lorica of this species is rigid, of very irregularly prismatic form 

 and rhomboid in cross section. It has a prominent dorsal keel 

 which begins at the anterior sinus and continues to the posterior 

 end of the lorica; its height is nearly uniform in the anterior half, 

 about one-third of the dorso-ventral depth of the body, and from 

 there decreases gradually. The cross section is variable; it may 

 be as wide as in figure 5, but is usually narrow and similar to L. 

 oxysternon, shown in figure 10. Immediately behind the middle the 

 keel has four transverse folds, those on the right side alternating 

 with identical plications on the left side; they are most prominent 

 at their dorsal extremity and cause the upper edge of the keel to 

 assume a zigzag course, as shown in the dorsal view, figure 3. A 

 lateral rib or ridge begins immediately behind the anterior margin 

 of the lorica and continues to the posterior end; it is bifurcate 

 anteriorly and its course is somewhat irregular, but follows approxi- 

 mately the lateral mid-hne of the body, curving upward at the foot 

 opening. Near the middle of the body two transverse ridges, with 

 a shght posterior inclination, start from the lateral ridge and dis- 

 appear before they reach the dorsal keel. On the ventral surface 

 of the body a median ridge begins near the anterior sinus and 

 reaches as far as the middle of the body, where it joins a curved 

 transverse ridge, which passes entirely across the ventral plate and 

 joins the lateral ridges. From the transverse ridge the ventral 

 plate is rather sharply inclined toward the foot opening, but no 

 groove is present. The dorso-ventral depth of the body is approxi- 

 mately equal to its width, about three-fifths of the length of the 

 lorica. 



The anterior margin of the lorica is truncate and provided with a 

 series of denticulations, about 20 in number, decreasing gradually 

 in size from the ventral to the dorsal edge. Neither the general 



