THE CASTNIAD^. 103 



Gf the aberrant forms nothing can here be said, since 

 the group itself has hitherto received but little attention. 



{99-) The Zyganidce, or more properly the Athero- 

 cerid(B (since the former name has long ago been em- 

 ployed in Ichthyology,) is the most extensive and varied 

 family of the whole tribe. Like the last, they are day 

 flying insects, small in size, but richly coloured ; vpith 

 fusiform, but generally pectinated, antennae, and very 

 small posterior wings : their structure is altogether 

 weak, and their flight slow and feeble. A few ex- 

 amples of one of the minor groups occur both in 

 Europe and Britain, but the major part inhabit the 

 tropical latitudes of America and India. The typical 

 groups are distinguished by their clear and transparent 

 wings ; but they are readily known from the brush- 

 tailed SesicB of Europe, by having no tufts at the end 

 of their abdomen ; and this part is also much thicker. 

 The metamorphosis of this family has been admirably 

 illustrated by Stoll, in his supplementary volume to 

 Cramer. The larva is onisciform ; but is either covered 

 ■with tufts of long hairs disposed in bunches or fas- 

 ciculi, or by elevated soft protuberances. The pupa 

 is always enclosed either in a cocoon, or in a fusiform 

 strong web, attached to plants. The resemblance be- 

 tween many of these insects and the Australian family 

 of AgaristidcB * is so close, that nothing but a close in- 

 vestigation will determine the genera respectively be- 

 longing to each. This is, perhaps, the most interesting 

 group in the whole tribe ; since we find representations 

 of every order, and of nearly every family, of lepido- 

 pterous insects ; many put on the appearance of wasps, 

 bees, beetles, moths, butterflies, flies, &c. ; and the 

 resemblance is so exact, that even an experienced eye 

 ■will not at first detect the difference. 



(100.) The CastniadcB, or moth sphinxes, conclude 

 our sketch of this tribe. This is a very peculiar family, 

 which, from their economy being entirely unknown, has 



» Some few American insects, however, enter into this group, 

 H 4 



