from the Island of Marajo^ Brazil. 297 



pectoral spines shorter than tlie head, the body less elono^ate, 

 the ienf^th of the head barely four times in the total, and the 

 supraoccipital bone broader than long. Dr. and Mrs. EigcMi- 

 niann have already drawn attention to the great variation in 

 the length of the spines in this species, and observed thcni to 

 be shorter in specimens from Para. 



35. Cetopsis ccccutiens, Licht. 



36. Doras costatus, L. S. 



The single specimen, 220 millim. long, has a very 

 puzzling appearance, owing to the absence of the caudal 

 peduncle. The posterior end of the tail must have been 

 accidentally amputated, and the shape of the well-developed 

 caudal fin points to neogenesis. The posterior scutes being 

 missing, with the caudal peduncle, the lateral line numbers 

 only 23. 



37. Doras WeJdelU, Cast. 



38. Doras dorsalis, C & V. 



39. Callichthys littoral is, Hancock. P. 



40. Plecostomus bicirr/iosus, Gron. M., P. 



41. Liposa)'cus pardalis, (Jast. S. 



42. ChiHostomus spinosus, Cast. 



43. ChcBtostomus cirrhosus, Val. 



44. Aspredo coti/lophorus, Bl. M., P. 



Characinidae. 



45. Macrodon trahira, Bl. Sclin. P. 



46. Macrodon intermedius, Gthr. P. 



47. Erythrinus unitceniatus, Spix. P., S. 



48. Hemiodus microcephalus , Gthr. 



49. Anostomus fasciatus, Ag. S. 



50. Leporinus affinis, Gthr. 



51. Tetragonopterus maculatus, L. 



52. Brycon brevicauda, Gthr. 



53. Piabuca argentina, L. 



54. Anacyrtus Myersii, Gill. 



55. Serrasahno serrulatus, C. & V. S. 



56. Serrasalmo piraya, Cuv. P. 



Ann. & Mag. N. Hist. JSer. 6. Vol. xx. 21 



