Head and mouth-apparatus of the larva of  Pachyneura sp.  ( Pachyneuridae).
1 -- head, dorsal view.  2 -- head, ventral view.
3 -- Mandible.  4 -- Maxilla, ventral view.
fr = frontal plate,  lpl = side-plate of head-capsule,  t = tentorium,  lbr = upper lip (labrum),  md = mandible,  mx = maxilla,  p.mx = palp of maxilla,  lb = lower lip (labium),  lac = lacinia,  st = stipes,  crd = cardo.
(After KRIVOSJEINA, 1969)