LARVAL FORMS OF COLEOPTERA 



Silphid association: 



8. Mandible with apex simple, recurved, and bent away from the 



sagittal plane of the larva. (Ligiila rounded and entire.) 

 Platypsijllidae (pi. 12 E-I, K) 

 Mandible with apex differently shaped, never recurved 9 



9. Galea present ; often developed as a small, hairy lobe on top of 



lacinia. (Ligula bi- or trilobed) 10 



Mala maxillaris simple. (Ligula either deeply bilobed, or en- 

 tire, or absent)^- 12 



10. Lacinia with entire surface asperate ; terminal joint of maxil- 



lary palpus subulate ; ligula trilobed. 



Scaphidiidae (pi. 12 A-D, J) 

 Lacinia not asperate or only along posterior margin ; terminal 

 joint of maxillary palpus not subulate; ligula bilobed 11 



11. Dorsal shields small, the abdominal ones quadrispinose ; ventral 



surface whitish and soft 



Silphidae-NecropJiorinae 

 Dorsal shields large, usually laterally produced with posterior 

 angles acuminate; ventral surface with well sclerotized 

 shields Silphidae-Silphinae^'^ (pi. 13 A-J) 



12. Ligula either deeply bilobed anteriorly, or absent ; nasale pres- 



ent 22 



Ligula entire anteriorly; labrum distinct, often movable 13 



Oxyporine association: 



13. Mandible narrowed at the middle, apically bifid and finely mu- 



cronate. (Ligula small and quadrate.) 



Staphylinidae-Oxyporinae^^ 

 Mandible different .' 14 



14. Ligula broad, anteriorly either rounded, straight, or slightly 



emarginate 15 



Ligula conical, often transversely bipartite at base 18 



15. Mandible with suddenly dilated molarlike base. (Apically 



with three or four teeth and ocelli several in number) 16 



Mandible with no molarlike base ^^ 17 



^^ The mala is crowned in several species of Bledius and in Syn- 

 tomiiim with a hairy, rounded projection which might be inter- 

 preted as a vestigial galea, but the ligula is simple and rounded. 



^^ The anatomical details of head and body have a primitive 

 character ; the systematic relationship to the oxyteline association 

 is rather remote, and the systematic position somewhat isolated. 



^* In the aleocharine genera Leptusa and Silusa the base is some- 

 what dilated, but the apex is bifid or entire and only one ocellus is 

 present. 



27 



