EIGENMANN: the PYGIDIID.E, a family of south AMERICAN CATFISHES. 307 



k. Caudal emargiiuite; (irigiu of ilnrsal cciuidistaut from tij} of caudal and opercle or pre- 

 oporcle, its distance from the caudal 1.5-I.S in its distance from the snout; head five in 

 the length; sides and hack with numerous dark spots, those along the middle of the 

 sides forming a distinct row, sometimes confluent along the anterior half of the body. 



36. banneaui Eigonmann. 

 kk. Caudal truncate or rounded. 



/. Dorsal, anal, and caudal truncate; origin of dorsal equidistant from tip of caudal and 

 pre-opercle, its distance from the base of the middle caudal rays l.G in its distance 

 from the snout; sides with a faint l)road l)and, oversown like the back with spots 



about the size of the eye 37. spilosoma Regan. 



//. Dorsal and anal rounded. 



m. Lateral band above the middle; maxillary l)arl)els exteniliug to the axil. 



;(. Caudal triincate-rounded; origin of dorsal equidistant from tip of caudal 

 and eye or nasal barbel, its distance from the caudal about 1.4 in its dis- 

 tance from the snout; the lateral band or row of spots above the middle, 

 from the ui)per part of the gill-o|)ening to above the middle of the caudal. 



oS. dorsostriatum Eigenmann. 



nil. Harbels very short, about reaching thi' eye; origin of dorsal e(iuidistant 



from tip of caudal and opercle, a faint lateral band, sides reticulated, 



first pectoral ray not prolonged 39. venulosum Steindachner. 



mm. Lateral band, if present, in the middle of the sides. 



0. Origin of dorsal equidistant from tip of caudal and nasal barbel, its 

 distance from the base of the middle caudal rays about 1.4 in its 

 distance from the snout; a lateral band increasing in width to the 

 caudal; middorsal area dark, a dark stripe between the lateral stripe 

 and the dorsal stripe in front of the dorsal. 



40. latistriatum Eigenmann. 

 im. Origin of dorsal equidistant from tip of caudal and a point between the 

 middle of the pectoral and the pre-opercle, its distance from the 

 mitldlc caudal rays l.S-2 in its distance from the snout. 

 /;. Maxillary barbel reaching a little beyond the axil or shorter; color 

 very variable, plain, or with one to three lateral stripes; origin of 

 the dorsal typically equidistant from tip of caudal and midiUe of 



pectoral rays 41. striatum Meek & Hildebrand. 



/*/(. Maxillary barbel reaching to near the end of the lower pectoral ray, 

 longer than the head; origin of dorsal equidistant from tip of caudal 



and opercular spines 42. regani Eigenmann. 



000. Distance between origin of dorsal and caudal 2.2-2.4 in its distance from 

 the snout; head as broad as long; eye in the middle of the head; distance 

 between base of last anal ray and the caudal 5.4 in the length. An 

 indistinct darker stripe along the midille of the side and traces of some 

 darker spots 43. retropinne (Regan). 



23. Pygidium laticeps (Kner). 

 Trichomyderus laticeps Kner, Sb. Acad. Wiss. Miinchen, 1863, p. 228; Kner & 

 Steindachner, Abhandl. K. Bayer. Akad. Wiss., 11. CL, Vol. X, Part I, 1864, 



