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Pierinae are allied to oiir common Brimstone-yel- 

 low butterflies, and tlie third to our White-spotted 

 Cabbage butterflies. The former, however, My- 

 lothrites and Cohates, belong to distinctly tropical 

 types, referable again to the Indo- Malayan or 

 Austro-Malayan regions; their larvae doubtless 

 fed on legmninous plants, which have been found 

 in abundance both at Aix and Radoboj, from which 

 these species come. The white butterfly belongs 

 to the existing genus Pontia, whose present geo- 

 graphical relations are almost precisely those of 

 Eugonia mentioned above, though the genus itself 

 is far better represented to-day in Europe than in 

 America ; their larvae feed generally on Crucif erae, 

 but these are plants of a nature hardly admitting 

 of preservation in a fossil state and are excessively 

 rare in the European tertiaries ; none have been 

 found at Radoboj, whence this butterfly comes, the 

 most closely aUied being a species of Terminaha. 



The Papihonid is an interesting insect belonging 

 to a striking and rather aberrant group. From 

 its aflinities to the existing Thais, it is called 

 Thaites. Thais is confined to-day to the Mediter- 

 ranean district, within which Aix, its place of de- 

 posit, belongs. It probably fed on Aristolochia, 

 and while this genus of plants has not yet been 



