LARVAL FORMS OF COLEOPTERA 



3. Epicranial halves meeting ventrally forming a transverse 



bridge 4 



Epicranial halves not meeting ventrally. (Subfacial sinus in- 

 complete or not present ; tenth abdominal segment bearing 

 retractile appendices) 8 



4. Nasale long, spatulate, distally with median emargination ; 



ventral epicranial bridge narrow and band-shaped ; cardo 

 absent ; body segments with dorsal shields*'^ 



Homolisidae 

 Nasale short ; ventral epicranial bridge broad, sagittally about 

 half as long as cranium ; cardo present ; body segments 

 fleshy, with velvety pubescence interspersed with fine setae. 

 (Thoracic and most of abdominal segments with a pair of 

 dorsal glands; subfacial sinus deep)''- 5 



5. ]\Iandible entirely without retinaculum ; mandibular canal al- 



most closed longitudinally, and distally having an oval open- 

 ing. (Anterior margin of nasale projecting, substriangular, 

 but without median grainlike tooth between a pair of longi- 

 tudinal grooves Cantharidae-Malihinae (pi. 77 



B-G) 

 Mandible ^^itll a large retinaculum (except in Podahrus, where 

 it is small and tuberculiform) ; mandibular canal open longi- 

 tudinally and without a special distal opening 6 



6. Maxilla without free, jointlike galea ; anterior nasal margin 



multi-serrate without a median grainlike tooth visible from 



above Caniharidae - Chaidiognathmae 



(pi. 78 A-I) 

 Maxilla with free, conical, one- or two-jointed galea ; anterior 

 nasal margin straight with a projecting median grainlike 

 tooth between a pair of short longitudinal grooves 7 



very reduced membranous antennae, mouthparts and legs. The 

 characterization given above refers to the larval instars prior to the 

 last one. See article by E. C. Rosenberg (Ent. Medd. Ser. 2, vol. 3, 

 1909, two plates). 



«i Bertkau, P.. Dent. Ent. Ztsehr., 1891, pp. 37-42, one plate. 



Verhoeff, K. AV., Zur Kenntnis der Canthariden-Larven, Archiv 

 fiir Naturgeschichte, vol. 89, A, Heft 1, 1923, pp. 110-137, one plate. 



''- According to Verhoeff, K. W. (Zur Entwicklung, IMorphol- 

 ogie und Biologic der Vorlarven und Larven der Canthariden, 

 Archiv. fiir Naturgeschichte, vol. 83, A, Sept. 2, 1917, pp. 102-140, 

 one plate), foetornetamorphosis occurs in members of the family 

 Cantharidae, two free-living foetal instars with vestigial antennae, 

 mouthparts and legs appearing before the first real larval instar. 

 This first instar itself differs only in minor characters, for instance 

 in the proportional length of the joints of the antennae and the 

 maxillary palpi, from the rest of the larval instars. 



47 



