This Genus, which so beautifully unites the Tetithr^dhiidce 

 with the Uroceridce, evidently belongs to the family Xiphydri- 

 fli(^ of Leach, although Dalman in his valuable paper upon 

 this Genus in the Stockholm Transactions (which are well 

 worth the perusal of the entomologist) considers that it be- 

 longs to the Urocer'idcE: the ample wings, however, and large 

 stigma bear considerable affinity to the genus Lyda, whilst it 

 cannot be denied that the compressed oviduct brings it close 

 to Xiphydria. Dalman, in his description, has overlooked the 

 twelfth joint of the antennae, which is the smallest, and also 

 one of the joints of the labial palpi, which he describes as only 

 3-jointed. Although the structure of this insect is altogether 

 remarkable, no part is, I think, more curious than the maxil- 

 lary palpi, which upon the insect look like feet; and from the 

 legs being placed far behind, it is not improbable that they 

 may occasionally be employed like those members : the second 

 and third joints are hollow, which probably enables the in- 

 sect to fold them close for protection, and the terminal joint 

 is perfectly flexible. 



Of this rare and interesting insect I have three females, 

 taken by myself many years back upon umbelliferous plants in 

 the vicinity of pines, in Norfolk, where those trees abound ; 

 and Mr. Stephens has one which was taken in the neighbour- 

 hood of London. The male I have never seen ; but from the 

 description, and an excellent figure given by Dalman, it ap- 

 pears to differ from the female only in being much smaller, 

 and in its abdomen, which is more cylindric, rounded and 

 simple at the anus. Another species much larger, called 

 X. longula by the same author, has been taken in Sweden by 

 Gyllenhal. 



Our species appears not to be uncommon in Sweden, where 

 it is said to be found upon Pimis sylvestris (PI. 7.) during the 

 month of July. Chccrophyllum sylvestre {y^'A^ Chervil) being 

 the umbelliferous plant upon which I believe my specimens 

 were taken, it is figured in the Plate. 



