COLEOPTERA 



431 



Prothorax elongate ; the front coxae minute, globular separated by a slender 

 process projecting backwards a little beyond them. The middle coxae (Plate XVI. fig. 1 1) 

 with small circular acetabula which touch one another. The metasternum is very elongate. 

 The abdomen consists of five ventral plates, the first to the fourth subequal in length, 

 the first a little the longer, the fifth about twice as long as the fourth. 



Tarsi (Plate XVI. fig. 9) 4-jointed with the basal three joints short, inserted a little 

 above the tip of the tibia in an excavation so that the basal joint escapes observation. 



The affinities of this minute beetle are very obscure. Notwithstanding its very 

 elongate form it has considerable resemblance to Holoparamec7is of the division Mero- 

 physiini. The members of this group have however only three joints to the feet whereas 

 I am fairly certain that there are four in Derolaf/irus. I therefore place the genus in 

 Colydiidae. I have elsewhere expressed the opinion that the Merophysiini should be 

 associated with the Colydiidae, and Derolaihrtis lends additional support to this view. 

 I cannot see the parts of the mouth. D. S. 



DerolatJirus atoimis, sp. nov. 



Perangustus, subdepressus, testaceus, obsolete punctatus, estriatus. Long. corp. 

 f mm. lat. vix \ mm. 



Plate XVI. fig. 8. 



There is very little to describe about this tiny species. The body bears a few erect 

 short setae. The outline and proportions will be appreciated from the figure. 



Two specimens ; and two others very much broken. There are unfortunately no 

 particulars as to its habitat. 



Hab. Oahu (Perkins). D. S. 



Fam. DISCOLOMIDAE\ 



Discolomidac Horn, P. Am. Phil. Soc. xvii. 1S78, p. 556. 



Discolonimae Sharp, Biol. Centr.-Am. Col. 11. i. p. 495. 



Pseudocorylophidae Matthews, Mon. Corylophidae, London, 1899, p. 197. 



Coxae omnes transversae, sed ex parte majore occultae ; tantum pars apicalis 

 globulosa aperta est. 



The erection of a family Discolomidae was proposed by Horn to include the genera 

 Discoloma and Hyberis { = Notiophygus). He states that the posterior coxae are 

 (apparently) completely closed in by the metasternum and first abdominal segment, the 

 metasternal side pieces not reaching them as they do in Colydiidae. 



Dr Sharp (op. cit. p. 496) showed that Horn had taken quite an erroneous view of 

 the hind co.xae. When the abdomen is dissected off, the superficial appearance is seen 

 to be quite deceptive. The coxae are really large, only the globular ending, where 



' By Hugh Scott. 

 F. n. III. 56 



