genera and species of the group of PsyllidcB. 473 

 Explanation of Plates. 



PLATE XVIII. 

 No. 1. — Psylla Diovauce. 



1, elytron ; la, head, front view ; 16, do., side view ; Ic, an- 



tenna ; Id, genitalia {^), as seen from the side; le, do., as 

 seen fr-om behind ; 1/, leaf, showing form of galls made ; 

 Ig, top or cover of a gall. 



No. 2. — Neolithus fasciatus. 



2, elytron ; 2(1, head, front view ; 26, do., side view ; 2c, antenna ; 



2(?, genitalia ((? ), as seen from the side ; 2e, do., as seen from 

 behind ; 2/, twig, with gall, natural size. 



No. 3. — Tliea trigutta. 



3, elytron ; 3«, head, front view ; 36, do., side view ; 3c, antenna ; 



3(?, genitalia (^), as seen from the side. 



No. 4. — Phytolyma lata. 



4, elytron and wing ; 4a, head, front view ; 46, do., side view ; 



4c, antenna; 4id, genitalia (<?), as seen from the side ; 4e, 

 do., as seen from behind ; 4/, portion of leaf showing form 

 of gall. 



No. 5. — Phyllolyma fracticosta. 



5, elytron ; 5a, head, front view ; 56, do., side view ; 5c, antenna ; 



5d, genitalia, as seen from the side ; 5e, do., as seen from 

 behind. 



PLATE XIX. 

 No. 1. — Psylla arctica. 



1, elytron ; la, head, front view ; 16, do., side view ; Ic, do., side 



view : Id, genitalia ( j ), as seen fr'om the side. 



No. 2. — Petalolyma basalis. 



2, elytron ; 2a, head, front view ; 26, do., side view ; 2c, antenna ; 



2d, one of the 3rd paii' of legs ; 2e, genitalia (<? ), as seen from 

 the side ; 2/, do., as seen from behind. 



No. 3. — Creiis longipenyiis. 



3, elytron ; 3a, head, front view : 36, do., side view ; 3c, antenna i 



'dd, genitalia of P. livioides, Walker, as seen from the side ; 

 3(i', do., as seen from behind ; 3e, genitalia of Livia longi- 

 2>ennis, Walker, as seen from the side ; So', do., as seen from 

 behind. 



No. 4. — Carsidara marginalis. 



4, elytron ; 4a, head, front view ; 46, do., side view ; 4c, antenna; 



Ad, one of the 3rd pair of legs ; 4e, genitaha {3^), as seen 

 from the side ; 4/, do., as seen fr-om benind. 



No" 5. — Tyora congrua, 



6, elytron and wing ; 5a, one of the 3rd pair of legs ; 56, genitalia 



((?), as seen from the side ; 5c, do., as seen from behind. 



