396 CALIFORNIA ACADEMY OF SCIENCES. 



Eye 5| in the snout, dh in the head, 3 in the interor- 

 bital. 



A large subcircular patch of minute granular scutes 

 on the center of the belly; a triangular patch between 

 the gill-opening and the rictus; ventral surface otherwise 

 naked. 



Base of the dorsal fin 2 in its distance from the adipose 

 fin; 7 plates between the spine of the adipose and the 

 caudal. 



Caudal equal lobed, the shorter ray 2 in the head. 



Light brown marbled with darker; tips of the caudal 

 dusky. 



Lat. 1. 28. A. 6. Head 3i. 



One specimen .09 m. Juiz de Fora, Rio Parahyba. 

 Thayer Expedition. 



Two specimens .085 m. Goyaz. These two specimens 

 collected by Senhor Honorio have large dusky spots on 

 the rays of all the fins. 



LXXXII. Plecostomus. 



Plecostomus Gronow, " Mus. i, 24, 1758;" id. Zooph. 

 127, 1863 (sp). 



Plecostomus Bleeker, Nederl. Tijdschr. Dierk. i, 77, 1863 

 (brasiliensis =^ jdecostomns. ) 



Hyjjostomus Lacepede, Hist. Nat. Poiss. v, 144, 1803 

 (giiacari = plecostomus. ) 



Hypostomus Guv. & Val. xv, 489 (plecostomus). 



Type: Plecostomus hraziliensis Bleeker. 



Habitat: Cordova and Rio Plata to Guiana region 

 and Rio Magdalena; Amazon to the Ambyiacu; Guaya- 

 quil. 



In a foot note, page 127 of his ZoophylaciiSm, Gronow 

 says: 



" Species subsequentes 391 and 392 hue proprie non 

 pertinent, ut pag 28 monui; ob labia revoluta huic gen- 



