TERACOLUS. I93 



into genera ; and hence they have been united into a single 

 genus by Dr. Butler, in which he has been followed by Mr. 

 Trimen, who formerly treated Idmais as distinct. Schatz, how- 

 ever, though admitting the absence of well-marked generic 

 characters, keeps the three genera provisionally separate, be- 

 cause most of the species belonging to each can readily be 

 separated at a glance by their colour and pattern ; and he 

 thinks it probable that these differences may be correlated in 

 their earlier stages. Mr. Trimen, while including all the species 

 under the smgle genus Teracolus, divides them into nineteen 

 sections ; and although it is not likely that all these will ulti- 

 mately be raised to generic rank, yet the mass of species which 

 they include will certainly be sub-divided sooner or later, and 

 therefore I prefer to treat the three best known genera sepa- 

 rately, giving the generic characters, which mostly apply to all 

 three, under the genus Callosuiie. The characters of Mr. Tri- 

 men's first division, in which he includes only the type of Tera- 

 colus, are given by him as follows : — 



"General structure robust; wings thick. Antennae rather 

 short and thick, with broad blunt club. Fore-wings acute in 

 both sexes j hind-wings with a fringe of hairs on costa near base.* 

 First and second sub-costal nervules of fore-wings closely ap- 

 proximate ; hind-wings with discoidal cell rather more than 

 half their length ; costa and costal nervure strongly arched ; 

 second sub-costal nervule originating some distance before ex- 

 tremity of discoidal cell." 



Teracolus subfasciatiis^ Swainson {Ptychopteryx bohemani^ 

 Wallcngren), though widely distributed in Southern Africa, 



* Mr. Trimen remarks in a note : *' This fringe of hairs (which occurs 

 in both sexes) is quite peculiar to T. siihfasciatns , no other species in the 

 same genus possessing it. This character occurs, however, in Eronia leda.'" 

 Ought it not to be considered generic, as Wallcngren, who first discovered it, 

 thought it to be ? 



