SYSTEMATIC CATALOGUE OF FISHES. 



141 



I. Lateral margin of upper jaw formed by the maxillaries; premaxillaries not protractile. 



a. Size very small; jaws short, teeth villiform and of equal size Umbrid.e. 



aa. Size moderate to large; jaws produced and flattened, teeth cardiform and of unequal size. 



EsociD^. 

 a. Lateral margin of upper j aw formed by the premaxillaries, which are more or less protractile. 



b. Vent placed well backward; premaxillaries very protractile Pceciliid^. 



bb. Vent placed near throat; premaxillaries slightly protractile Amblyopsid^. 



Family UMBRID^. The .Mud Minnows. 



A family of small fresh-water fishes, interesting on account of their habits 

 and their peculiar distribution; of the three known species, one is found in Aus- 

 tria and two in the United States. The body is long, but little compressed; the 

 head broad; the lower jaw, premaxillaries, vomer, and palatines have bands of 

 villiform teeth; the broad maxillaries, which form the lateral margins of the 

 upper jaw, have no teeth; the branchial openings are wide, gill-rakers small, 

 branchiostegals 6 to 8; pseudobranchise glandular; no lateral line; scales firm, 

 regular, cycloid, covering body and head; fins small, dorsal single, placed well 

 backward but in front of anal; pectorals close together; air-bladder simple. 

 Oviparous, carnivorous fishes, inhabiting muddy ditches, and ponds and sluggish 

 streams overgrown with weeds; very hardy and able to live buried in mud; 

 sexes similar. 



Genus UMBRA Miiller. Mud Minnows. 



Characters of the genus are shown above.* One species is found locally. 

 (Umbra, shade.) 



119. UMBRA PYGM^A (DeKay). 

 "Mud-fish"; Mud Minnow. 



Leuciscus pygmteus DeKay, New York Fauna, Fishes, 1842, 214; Rockland County, N. Y. 



Umbra pygmwa, Jordan, 18896, 126; Tar River at Rocky Mount. Jordan & Evermann, 1890, 024, pi. xcix, 



fig. 268. 

 Umbra limi pygmcEa, Evermann & Cox, 1896, 305; tributary of Neuse River near Raleigh 



Fig. 48. Mud Minnow. Umbra pymoea. 



Diagnosis. — Form compact, oblong, slightly compressed, depth contained 4-5 times in 

 total length; head short and broad, .25 length of body; snout short, equal to eye, which enters 

 4.5 times in length of head; mouth moderate, jaws short; gill-slits wide; gill-rakers short and 



*.\n interesting review of these fishes has recently been published by Dr. Theodore Gill under the title 

 "A remarkable genus of fishes— the umbras", in Smithsonian Miscellaneous Collections, quarterly issue, vol. 

 i, 1904. i 



