414 KEPORT OF COMMISSIONER OF FISH AND FISHERIES. [72] 



78. PACHYPOPS ADSPERSUS. 



? Corvina grunniens Schomburgk, Nat. Libr. Fish. Guiana, 1843, 136 (RioEssequibo). 

 Pachyurus (Lepipterus) adspersus Steindachner, Ichtbyol. Beitr., viii,5, 1879 (Rio Para- 

 byba, Rio Doce, Rio Sau AntODio, Mucuri). 



Habitat. — Rivers of Brazil. 



We have examined numerous specimens of this species in the museum 

 at Cambridge from Rio Uoce, Santa Clara, Rio San Antonio, and Men- 

 chez. The specimen described, 15 inches in length, is from the Rio 

 Doce. 



The scanty description of Corvina grunniens indicates some river 

 Scisenoid, with distinctly spotted dorsal and anal fins, and with the fin 

 rays D. IX, 32 ; A. II, 7. The account comes nearest among known species 

 to Pachypops adspersus, and if this species occurs in the Essequibo it 

 should probably stand as Pachyjjops grunniens. But without a better 

 knowledge of the local fauna of Guiana, such an identification would 

 be premature. 



Genus XVII.— POLYCIRRHUS. 



Polycirrhus Boconrt, Nouv. Arcb. Mus. d'Hist. Nat., iv, 22, 1868 (dumerili). 



Type : Polycirrhus dumerili Bocourt. 



This genus is composed of three species of Scirenoid fishes, distin- 

 guished from Micropogon chiefly by the absence of seme on the pre- 

 opercle, and from Genyonemus by having the normal number of dorsal 

 spines. All the known species are marked by well-defined dark cross- 

 bands, and all belong to the fauna of South America. 



ANALYSIS OF SPECIES OF POLYCIRRHUS. 



a. Dorsal rays about IX-I, 22 ; caudal fiu double truncate ; body ratber elongate, tbe 

 back somewhat elevated, tbe head low aud small; profile steep; ventral outline 

 straightisb ; snout not very sbort, somewhat acute, 3^ in head ; iuterorbital 

 area broad, convex, 3 in head; eye 5^; mouth small, entirely inferior, max- 

 illary extending past middle of eye, 2§- in head ; teeth small, villiform, the 

 outer scarcely larger ; preopercle rounded, its edge with soft cilia ; third 

 dorsal spine 3 in head ; soft dorsal with' a scaly sheath, its membranes with 

 small scales; ventrals filiform at tip, 1^ in head; anal inserted well forward, 

 its second spine 2f in head ; caudal double truncate ; lateral line much arched 

 anteriorly. Color, bluish-gray, silvery below ; 6 rather broad distinct cross- 

 bars extending down to edge of belly ; two inconspicuous dark cross-bars on 

 head ; lower fins pale. Head 3| to 3f in length ; depth 3* to 3J. D. IX-I, 

 22 to 25 ; A. II, 7 or 8 ; scales 6-47 to 52-9 Dumerili, 79. 



aa. Dorsal rays X-I, 26 to 32. 



b. Caudal fin obliquely truncate, or somewhat pointed. Dorsal rays X-I, 29 to 31; 

 snout short, 3| to 4£ in head ; body more elongate than in P. dumerili, the 

 snout lower, shorter, aud more pointed ; maxillary 3^ to 3^ in head; gill-rakers 

 minute ; fins scaly ; soft dorsal rays 3 in head ; eye 4 J to 6 ; longest dorsal 

 spine 2^ ; caudal ly ff in head ; second anal spine very small, 4| in head ; pectoral 

 1J; preopercle ciliated on its membranous border. Coloration less marked 

 than in P. dumerili, the darker cross-bands narrower, more numerous (about 

 8), and less sharply defined ; the anterior band sometimes reduced to a large 

 round black blotch above base of pectoral; pectoral mostly dusky. Head 4; 

 depth 3$. D. X-I, 29 to 31 ; A. II, 8 ; scales about 7-58-11 . . Brasiliexsis, SO. 



