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On the Potato Gruh of Tasmania. By Capt. H. Beethon^ 

 H.E.I.O.S. {Bead \Uh March, 1855.] 



The grub, whicli did so much injury to the Potato crops in 

 certain parts of this island last year, and which threatens 

 during the present season to commit still further devastation, 

 is the production of a small moth of the Tineidse family, 

 and appears to be identical with the insect which has of 

 late years been making such ravages amongst the tubers in 

 New Zealand. In fact, it is by no means improbable that 

 it was introduced into Tasmania in some infected importations 

 from that country. 



The moth is about one-third of an inch in length, of a 

 silvery grey colour, barred with brown, with the usual jointed 

 antennae, trunk, and other peculiarities of formation which 

 characterise the order " Lepidoptera." It is distinguished 

 from many others of the class by a peculiar pair of palpi, 

 springing from the base of the trunk, and curving back- 

 ward over the head. The ova are elliptical in shape, of the 

 size of a very minute grain of sand, and pearly white in hue. 

 The larva, when full-grown, are about five-twelfths of an inch 

 in length, of a semi-transparent yellowish white, forcibly 

 reminding one of the colour of the white currant, to which is 

 occasionally superadded a tinge of pink. i\s in other 

 members of the order, they are furnished with six thoracic 

 legs ; and four of the remaining eight sections of the body 

 are provided with pro-legs. The pupa, or chrysahs, is of a 

 dark amber colour, little more than half the length of the 

 full-grown larva, and is ordinarily placed in one of the eyes 



