43 



The genera to which they are referred are characterized in the 

 synopsis of the sub-family of Pimelodinge. 



Genus Ictalurus (Raf) Gill. 



All of the following species are members of this genus ; they are 

 arranged provisionally, nearly in the order of time in which they 

 were described by their nomenclators. 



Ictalurus ccerulescens=zSilurus punctatus it«/. = Silurus pallidus 

 itff/ = Silurus coerulescens it a/. i= Pimelodus maculatus Raf.z=i 

 Pimelodus coerulescens (Raf-) Kirttand. 



Ictalurus furcatus=r Pimelodus cauda-furcatus Ze.>JMeur = Pimelodus 

 furcatus auct. 



Ictalurus furcifer^z Pimelodus furcifer Veil. 



Ictalurus gracilis = Pimelodus gracilis i7c»M^^z= Pimelodus Houghii 

 Girard. 



Ictalurus Beadlei^zSynechoglanls Beadlei Gill. 



Ictalurus olivaceusm Pimelodus olivaceus Girard. 



Ictalurus affinis = Pimelodus affinis Baird and Girard (1854). 



Ictalurus vulpes=: Pimelodus vulpes Girard. 



Ictalurus megalops:= Pimelodus megalops Girard. 



The following species perhaps belong also to this genus, but the 

 insufficient descriptions given of them, leave it doubtful whether they 

 are Ictaluri or Amiuri. 



Pimelodus lupus Girard. 



Pimelodus graciosus Girard. 



A species of this genus is described in Griffith's edition of the 

 " Regne Animal " of Cuvier as the Pimelodus Cranchii. As the 

 figure is itself very poor, and as there is no description nor any men- 

 tion of the habitat of the species, it is irrecognizable, and cannot be 

 retained as a valid sp»ecies of the genus. 



Ictalurus Simpsoxii Gill. 

 Head from the snout to the margin of operculum, forming twenty- 

 two hundredths (22-100) of the length from snout to end of median 

 caudal rays. Eyes large and oval, the longest diameter between a 

 fifth and sixth of the head's length. Maxillary barbels extending 

 beyond the opercular bones ; the nasal slender and scarcely longer 

 than the eye's diameter ; the external inframaxillary exceed half the 

 length of the maxillary, and are twice as long as the internal ones. 

 Eight branchiostegal rays. Dorsal fin commencing at the anterior 

 third of the length from the snout to the concave margin of the 

 caudal ; its spine is slender and three fourths as long as the longest 

 ray ; it is nearly edentulous behind. The process of the coracoid 

 bone of Owen projects beyond the base of the pectoral spine for a 

 distance equal to the interval between the snout and orbit. The 

 caudal fin is deeply forked, the longest ray being at least twice as 

 long as the central ones ; the latter form a ninth of the total length. 



