246 



SERIES II. — CLAV1C0RNIA. 



s.,Last joint of tarsi, long, claws large; head retractile, the mouth pro- 

 tected by the prosternum ; aquatic or subaquatic species. 



Family XXXIII. Parnhle, p. 675. 

 ss. Last joint of* tarsi moderate, claws normal; thorax (in our species) 

 with deep grooves ; mouth parts covered by a large mentum. 



Family XX. Rhyssodid^e, p. 558. 



Subseries C. TKTRAMERA CLAY WORM A. 



In this group (with the exception mentioned in key to subseries) , 

 the tarsi are four-jointed. The species live, for the most part, in 

 fungi, especially those growing on dead trees and logs; some are 

 subaquatic, living in mud or sand along the margin of water. 



KEY TO FAMILIES OF TETRAMERA CLAVICORNIA. 



a. Ventral segments all free and movable. 



b. Wings fringed with hairs ; very small, less than 2 mm. 



c. Hind coxae contiguous, with plates covering the thighs ; antenme 



nine-jointed, club two-jointed. 



Tribe '(VIII). Clambini, p. 291. 

 cc. Hind coxae separate, without plates ; tarsi apparently three-jointed, 

 the basal joint concealed by the notched second joint ; mandibles 

 with comb-like teeth. Family XV. Corylophtd.f:, p. 501. 



bb. Wings not fringed with hairs. 



d. Front coxse transverse ; body contractile ; length less than 2 mm. 



Tribe (XXVI). Cybocephalini, p. G47. 



dd. Front coxse not transverse. 

 e. Front coxse globose. 



f. Tarsi slender ; length less than 4 mm. 



Subfamily (XVII). Mycetwince, p. 534. 

 11. Tarsi more or less dilated and spongy beneath, the fourth joint 

 united with the fifth, so that only four are visible ; antennae 

 strongly clubbed. Family XVIII. Erotylid.e, p. 530. 



ee. Front coxse oval. 



g. Front coxse well separated by the horn-like prosternum. 



h. Form oval, depressed; head free; surface finely and densely 

 punctured and hairy; length less than 6 mm. 



Family XXIII. Mycetophagid,e, p. 582. 

 hh. Form cylindrical ; thorax prolonged over the head ; length 

 less than 3.5 mm. Family (XLVII). Cioid.f], p. 895. 



gg. Front coxse almost contiguous ; prosternum semimembranous ; 

 form small, rounded, convex; habits subaquatic ; length less 

 than 1 mm. Family XXXII. Georyssid^e, p. 675. 



aa. Ventral segments 1-4 firmly united, the fifth only being movable. 



i. Antennae of regular form ; tibise not dilated, not fitted for digging ; 



front and middle coxae small, globose ; length less than 6 mm. 



Family XIX. Colydiid^, p. 549. 



ii. Antennae short, the outer seven joints broad and short ; tibise dilated, 



armed with rows of spines and fitted for digging ; labrum and 

 mandibles projecting forward ; length less than 7 mm. 



Family XXXIV. Heterocerid/E, p. 082. 



