3138 Bulletin ^7, United States National Museum. 



Page 132. After Tachysurus melanopus (Gunther), insert the following: 

 200 (a). TACHYSURUS FEST.E (Boulenger). 



Head 4; depth 4; eye 6, above level of mouth, in anterior part of head. 

 D. 17; A. 23. Premaxillary band of teeth 4 times longer than broad, i;.s 

 width 2 in eye, or equal to width of groups of vomer and palatine 

 teeth, these last granular, forming 2 large, oblique groups, separated on 

 ^the median line by a space equal to ^ diameter of eye; width of head 1 

 in its length; occiput and occipital prolongation granular, the last as 

 long as wide, and with blunt spine; fontanelle narrow, commencing in a 

 groove between the anterior nostrils and reaching occiput, not reaching 

 occipital prolongation; barbels flattened: maxillary as long as head, reach- 

 ing beyond base of pectoral spine; external mandible a little shorter, 

 as long as the internal ; gill-membrane with a free border broken at the 

 isthmus; anal spine striated, 1 in head, its anterior edge feebly toothed 

 except at extremity, which has, like the posterior edge, stronger and 

 more retrorse teeth ; adipose dorsal twice as far from raj*ed dorsal as from 

 caudal, its base H in base of rayed dorsal; pectoral spine H in head, its 

 external edge furnished with a series of soft, small tubercles on its basal 

 half, anterior edge armed with feeble retrorse teeth; ventral shorter, 

 reaching origin of anal; caudal deeply forked; caudal peduncle twice as 

 long as deep; axillary pore present, much smaller than the nostril. Color 

 steel blue above, silvery below. This species closely resembles Taclnjsnrns 

 liropus, Bristol. Length 210 mm. One specimen known, from Narrangal, 

 Ecuador. (Boulenger.) (Named for the collector of the type, Dr. Enrico 

 Festa.) 



Arius festce, BOULENGER, Bollettino del Mua. di Zool. ed. Anat. Cornp. della Univ. di 

 Torino, Vol. xm, Ko. 329, 5, Dec. 2, 1898, Narrangal, Ecuador. 



Page 135. After Ictalurus meridionalis (Gunther), insert: 

 76(3). ISTLARIUS, Jordan & Snyder. 



Istlarius, JORDAN <fc SNYDER, Bull. U. S. Fish Cora. 1899 (1900), 118 (balsanus). 



Body rather deep and compressed; head not widened, nor greatly 

 depressed; eye large; lower jaw included; teeth in villiform bauds on 

 premaxillaries and dentaries; the premaxillary band convex anteriorly, 

 with a short angular posterior extension on each side, no division of 

 the band at symphysis; dentary band broad anteriorly, growing narrow 

 and pointed posteriorly, with a distinct median division; no teeth on 

 vomer or palatines; villiform teeth on upper and lower pharyngeals; 

 gill-rakers on first arch 17, long and slender; branchiostegals 8; air 

 bladder very large, extending almost to posterior end of body cavity, 

 divided by a transverse constriction into two parts of nearly equal 

 length, the anterior heart-shaped, posterior part oval; supraoccipital 

 bone widely separated from interspinal; humeral process short, almost 

 hidden by the skin; lateral line extending from below insertion of 

 dorsal to caudal; skin covered with minute, hairlike villi; skin of 

 head completely concealing bones of skull; barbels 8. Spines with 



