March, 1903.] BUSCK : NOTES ON Vl'ONOMEUTlU.E. 47 



retained by nearly all subsequent writers. It should stand for the genus 

 at present represented by the single species iiiucronella Scopoli. 



Wallengren also correctly divided the remaining European species 

 in two genera under the names Credcmiion and 1 railioma, of which 

 sylve/la Linne and asperella I ,inpe relatively may be regarded as types. 



The first of these names should be drop])ed for Hiibner's name 

 Abebcea (Verz. bek. Schmett., p. 408, 1816), which may ajjproiHi- 

 ately be restricted to this groujj. 



The Cerostoina group as here treated may briefly be defined as 

 including all Plutellidne with veins 6 and 7 in hindwing stalked. 

 The genera have the following characters in common. Labial palpi 

 with more or less developed porrected tuft on the underside of second 

 joint ; terminal joint i)ointed. Maxillary j)alpi present, moderately 

 developed, appressed or porrected.* 



Forewings more or less elongate, apex often produced or falcate ; 

 12 veins, 7 to termen, i /' furcate at base; veins 7 and 8 stalked or 

 separate, this character does not seem to have generic value in this 

 group, while the relative position of veins 2 and 3 in the forewing on 

 the contrary is found to furnish a good character. 



Hindwings about as broad or somewhat broader than forewings ; 

 costal edge nearly straight, dorsal edge evenly and but slightly rounded, 

 without sinuation below^ the apex, which is more or less jjointed ; 

 veins 6 and 7 long-stalked, all other veins separate. Tibia of hind 

 legs smooth. 



The genera may be separated by the following table: 



Forewings with erect scales 1 



Forewings smooth 2 



1. Veins 2 and 3 in forewings separate Trachoma Walleiti^reen 



Veins 2 and 3 in forewings stalked Therestis Hubncr 



2. Brush on second joint of labial palpi at most as long as terminal joint. 



Cerostoma LiUreil/f 



Brush on second joint longer than terminal joint 3 



3. Forewing sickle-shaped; veins 2 and 3 connate Harpipteryx Hiibncr 



Forewings not sickle-shaped; veins 2 and 3 distant Abebsea liulmer 



* Herrich-Schaeffer, Heinemann and other European writers state that the mav- 

 illary palpi are absent in the genus Tlwrestis and this belief has probably been the 

 principal reason why this genus alone has been retained separate; but the maxillary 

 palpi are merely obscured from view by the strongly developed labial palpi andean be 

 found by removing them. They are about as well developed as in any of the other 

 genera of the group. 



