South American Rotifer a. By J. Murray. 345 



120 yLt, length of toe 80 /a. The dorsal plate is a short ellipse trun- 

 cate at both ends. Both anterior margins are nearly straight, the 

 ventral rather lower and slightly excavate. The prominences on 

 each side of the foot appear to be homoLjgous with those of C. 

 hornemanni (Plate XIY, fig. 26), the toe tapers slightly, and near 

 the point has an abrupt shoulder which runs out into a sharp 

 point. The lateral view shows that the claw is excavated behind, 

 the front eds^e beino" unbroken. 



C. gra.ndis is not the largest member of the family ; C. minneso- 

 tensis Herrick (41) is considerably larger. It is the same animal 

 which Gosse afterwards (4-0) named C. ungulata, and is here 

 figured (Plate XIII, fig. 18), in order to give a scale for all the figures 

 accompanying this paper, which are all drawn to the same magni- 

 fication ( X 260). C. minnesotensis is distinguished from C. grandis 

 by the anterior spines, narrower dorsal plate, prominent posterior 

 lobe, and very long claw. 



C. g7rtndis is nearest to C. luna (Plate XIII, fig. 19), but that is 

 much smaller,' has deeply excavated anterior margins, and lacks 

 the triangular prominences on the foot. 



Hahitat. — In the very saline water of the lagoon near the 

 Botanic Gardens, Piio de Janeiro. 



Cathypna luna Miiller HG) Plate XIII, fig. 19. 



Syn. Cercaria luna Mull. 1776 {^6). 

 Euchlanis luna Ehr. 1831 \S6). 



Description. — Length of contracted lorica 150 /a, of dorsal plate 

 125 //,, of toe 55-60 /a ; breadth of dorsal plate 120 fju, of anterior 

 margin 60 /x. 



The dorsal plate is nearly as broad as long, and nearly round, 

 only slightly truncate at both ends ; the ventral plate is very little 

 narrower than the dorsal. The dorsal anterior margin is deeply 

 excavate, in three concavities, the two lateral being between the 

 dorsal and ventral angles. The anterior lateral angle is acute, 

 but cannot be said to form a spine. The ventral anterior margin 

 is a little more deeply excavate than the dorsal. Both lateral and 

 posterior sulci very deep. Posterior part of lorica prominent, 

 broad, rounded. Toe tapering, with conspicuous shoulder and claw. 



Hahitat. — Eio ; Punta Arenas ; a common animal almost every- 

 where. 



Catliypna leontina Turner (-54). Plate XIII, figs. 21a-21c. 



Syn. C. scutaria Stokes, C. macrodactyla Dad. 



Description. — J^arge, pyriform, with incised frontal margins 

 and large flat posterior process. Toes very long and slender, 

 sharply shouldered, and with long claw. 



