Jordan: Fossil Fishks from Riacho Dock. 25 



Hyperlofhus Ogilhy. (Rlt. Austr. Mus., I[, iS()3, 26. Type 

 Hyperlophns spnUellidcs, the "Sandy Sprat" of streams of 

 New South Wales.) 

 Maxillar\- broad; no teeth; mouth very small; mandible i:)rojecting; 

 branchiostegais four; dorsal inserted behind middle of body; ventrals 

 inserted before dorsal; dorsal scutes small; ventral scutes moderate; anal 

 of about nineteen rays; scales pectinate. Dr. Woodward regards Ilyper- 

 lophiis as a synonym of Diplomystiis, which is quite unlikely. One may 

 be too hasty in regarding living forms as identical with exlinct genera, 

 as well as too hasty in separating them. 



PoTAiM.\LOSA Ogilby. (Proc. Linnean Soc. N. S. W., XXI, 1897, 504. 

 Type Clupea nov(B-hoUandice C. & V. of streams of Australia.) 



Maxillary narrow; teeth present in jaws and palate; branchiostegais 

 eight; dorsal inserted before middle of body; anal small; ventrals under 

 front of dorsal scales large, smooth; dorsal scutes small; ventral scutes 

 moderate. 



Allied to Potavialosa are certain American species, typified by "Pota- 

 tfialosa" notacanthoides (Steindachner) of Chile. This species has the 

 form of an alewife; maxillary rather broad; no teeth; scales rather large 

 and firm, cuneate; dorsal and ventral scutes small; ventrals moderate, 

 under front of dorsal; anal short; fourteen rays; caudal scaly. This 

 species stands between Ellipes and Potamalosa. 



In any event, I think that we are justified in recognizing Ellipes, 

 Potamalosa, Hyperlophus, and Knightia as distinct subgenera, even if 

 we should wish to place all double-armored herrings in the single genus, 

 Diplomyslus. 



I. Ellipes branneri sp, nov. (Plate VIII, fig. 3.) 

 Type, a small, much compressed herring pressed flat in black shale, 

 from Riacho Doce, Alagoas, Brazil, J. C. Branner, collector. Total length 

 2 to 3^ inches. 



Head 3 in length to base of caudal; depth 2; length of longest rib a 

 shade more than length of head. Distance from snout to nape equal to 

 distance from nape to dorsal fin. Length of caudal portion of abdomi- 

 nal column equal to length of head and two-thirds greatest depth. Body 

 short and deep, the back not elevated ; the belly very convex and sharply 

 keeled, with about twenty sharp plates; plates in front of dorsal mostly 

 lost; those present small and entire; caudal peduncle deeper in front than 

 long. Head rather deeper than long. Maxillary more or less crushed 



