532 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.47. 



fact that in a later paper ^ Ehrenberg figures under the name stipitata 

 what is evidently a typical cochlearis. 



Keratella stipitata was found in collections from: Gatun Lake, 

 abundant; Brazos Brook Reservoir, collected in the middle, abund- 

 ant; creek flowing into Camacho Reservoir (3), few; Camacho Reser- 

 voir, conamon; stagnant pool at Empire (4), few; Rio Grande (6) 

 few; pond at Bohio (7), very abundant; Rio Grande Reservoir (5), 

 common; pond at Miraflores (12), conomon; the form without pos- 

 terior spine (tecta) in a bayou of the French Canal, 2 miles south of 

 Gatun, few. 



KERATELLA QUADRATA (Muller). 



Anuraea aculeata Ehrenberg, Abh. Akad. Wiss., Berlin (for 1831), 1832, p. 145. 

 In creek flowing into Camacho Reservoir (3) , few. 



NOTHOLCA LONGISPINA (Kellicott). 



A single specimen from a pond near Rio Chagres at Bohio (7). 



ANURAEOPSIS FISSA (Gosse). 



Anuraea Jissa Gosse, Ann. Mag. Nat. Hist., eer. 2, vol. 8, 1851, p. 202. 

 CaTabali (Gorgona) Reservoir, common; Rio Grande Reservoir (5), 

 few. 



MYTILINA TRIGONA (Gosse). 



Diplax trigona Gosse, Ann. Mag. Nat. Hist., ser. 2, vol. 8, 1851, p. 201. 

 A single specimen in a coUection from the raihoad bridge over 

 Black Swamp (1) ; stagnant pool at Empire (4), abundant. 



MYTILINA VENTRALIS (Ehrenberg). 



Salpina ventralis Ehrenberg, Abh. Akad. Wiss., BerHn (for 1831), 1832, p. 133 

 pi. 4, fig. 7. 



This species appears to be rare on the Isthmus; only single speci- 

 mens were found, in the following collections: Pool between Black 

 Swamp and Gatun (2) ; Rio Grande Reservoir (5) ; Rio Grande (6) ; 

 Rio Trinidad, above Agua Clara (10). 



EUCHLANIS DILATATA Ehrenberg. 



From a slow stream in garden of Isthmian Canal Commission, 

 Empire, common; stagnant pool by the railroad, north of bridge over 

 Black Swamp, few; pool between Black Swamp and Gatun (2), few; 

 stagnant pool at Empire (4), common; Rio Grande (6), few; Rio 

 Trinidad, at Escoval (11), few; pond at Miraflores (12), common. 



EUCHLANIS OROPHA Gosse. 



From a creek flowing into Camacho Reservoir (3), common; Rio 

 Trinidad, at Escoval (11), few. 



» Abh. Akad. Wiss., BerUn (for 1841), 1843, pp. 291-446, pis. 1-4. 



