516 Mr. D. Sharp and Mr. F. Muir on the Comparative 



Family TROGOSITIDAE (or Ostomidae, or Tcm.no- 

 chilidae). 



Forms examined : Temnoch.ila vircsccns Fabr., Mexico. 

 Alindria grandis Serv., Africa. Leperina, sp. n. ? aff. 

 adustae Pasc, Australia. Thymalus lirnhatus Fabr,, 

 Brockenhurst. 



Figs. 89 and 90 Pis. LVI and LVII. 



Tcmnochila virescens (Pi. LVI figs. 89, 89fl!.). 



Median lobe long, flattened laterally, formed by a trough-shaped 

 chitin plate (a) on ventral aspect and membrane on dorsal aspect [b), 

 with a chitin strut round median orifice at distal end (c). Tegmen 

 formed into a sheath ; lateral lobes distinct and only amalgamated at 

 base ; basal-piece large and tubular, chitinous on dorsal and ventral 

 aspects, membranous on sides. Internal sac undifferentiated. 



Alindria (jrandis is of the same type, but the division between 

 lateral lobes and the basal -piece is obliterated. 



Thymalus Hmlatus (PL LVII figs. 90, 90a). 



Median lobe long, straight, flattened laterally. Tegmen forming 

 a sheath with lateral lobes consolidated together on th.& ventral aspect, 

 basal-piece long, tubular, with a strong strut on the dorsal aspect 

 at base («). 



Leperina aff. adustae is of the same type but has the lateral lobes 

 free. 



It is possible that this type is a development of a trilobe 

 type through such a form as Aulonium. Byturus belongs 

 near this family. 



Family COLYDIIDAE. 



Forms examined : Unarsus halcewclli Pasc, New Zealand. 

 Tarphiomwncs indeniatus Woll., New Zealand. Aulonium 

 hidentatitm Fabr., Guatemala. Dcrctaphrus ignavtis Pasc, 

 Australia. Cerylon histeroidcs Fabr., England. 



Figs. 91-95 of PI. LVII relate to the above-named 

 forms. 



Enarsus hakcwelli (PI. LVII figs. 92, 92(r, 92&). 



Median lobe nearly as long as tegmen, chitinous on dorsal and 

 lateral aspects, membi'anous on ventral («) ; median orifice on ventral 

 aspect near apex. Tegmen consists of a large basal-piece formed of a 

 ventrally-placed sclerite, the dorsal aspect membranous, and a pair of 



