234 silukid^:. 



7. Plecostomus alatus. 



Casteln. Anim. Amer. Sud, Poiss. p. 41. pi. 20. fig. 1. 



D. 1/7. A. 5. P. 1/6. V. 1/5. L. lat. 27. 



Head depressed, with scarcely any prominence on the occiput and 

 on the nape; its length is a little more than one-fourth of the total 

 (without caudal) ; the diameter of the eye is one-half of the width 

 of the interorbital space. The middle of the extremity of the snout 

 is naked; interoperculum without spines. The lower side of the 

 head is naked, with the exception of a granulated elongate-ovate 

 space on each side of the anterior labial fold ; a similar granulated 

 patch between the mouth and the gill-opening. The thorax is 

 nearly entirely covered with granulations, whilst the sides of the 

 belly remain naked. Dorsal fin very high, the anterior rays being 

 much longer than the head ; the length of its base is rather more 

 than its distance from the second fin ; there are eight scutes between 

 the two fins. Caudal fin subtruncated, with the lower rays rather 

 longer than the upper. The pectoral spine is broad, extending to 

 the second third of the length of the ventral, and is covered above 

 with numerous slender curved spines. Thirteen scutes between anal 

 and caudal. Scutes of the body granulated, without keels ; post- 

 humeral ridge distinct, but obtuse. All parts with numerous small 

 round yellow spots ; each of the larger scutes has two or three of 

 these spots, the smaller ones only one. 



Minas Geraes. 



a. Skin: 17 inches long. River Cipo. From Mr. Ch. Cumberland's 

 Collection. — Vernac. name : Cascudo. 



8. Plecostomus anroguttatus. 



Ilypostomus auroguttatus, Sner, Hypostom. p. 2G9. taf. 2. fig. 3. 

 asperatus, Casteln. Anint Amer. Sud, Poiss. p. 41. pi. 20. fig. 2. 



D. 1/7. A. 5. 



Occiput and nape depressed; the length of the head is less than 

 one-third of the total (without caudal) ; snout very broad and obtuse, 

 semicircular, the head being as broad as long ; eye of moderate size, 

 its diameter being somewhat less than one-half of the width of the 

 interorbital space. Scutes of the body with scarcely any keels, but 

 with the margins spiny ; margins of the opercles with short spines. 

 Thi'oat, thorax, and belly with only a few small granulated patches, 

 otherwise naked. There are twelve or thirteen scutes between anal 

 and caudal. Lower jaw with about sixty thin, long, non-lobate 

 teeth on each side. Dorsal fin rather higher than long, the length 

 of its first ray being equal to that of the head. The pectoral spine 

 extends to the end of the ventral. Sides of the body with irregular 

 longish yellowish spots, sometimes confluent into bands. Fins with 

 similar spots. (Kiier.) 



Brazil. 



