BY T. G. SLOANE. 587 



and roundly inflated on inner side opposite origin of outer 

 lobe, sharply hooked ; apex extending forward greatly beyond 

 hook. Prothorax very little wider than head, punctate, light- 

 ly narrowed to base; sides lightly rounded, not ampliate; 

 lateral border terminating a little before base. Elytra nar- 

 row, parallel, interstices costate with summits nitid, biseriate- 

 ly punctate. Legs short ; tarsi short, penultimate joint of 

 anterior tarsi short, wide, emarginate. Type, jEnigma uni- 

 color Hope. 



Habits terrestrial. 



It is a terminal genus, not closely allied to any other. 



Helluodema unicolor Hope. 



^Enigma unicolor Hope, Proc. Ent. Soc, 1842, 47; Ann. 

 Nat. Hist., ix., 1842, 426: Ilelluomovpha bafesi Thomson, 

 Arch. Ent., 1857, 134: Helluodema batesi Castelnau, Trans. 

 Roy. Soc. Victoria, viii., 1868, 105; Gestro, Ann. Mus. Civ. 

 Genova, vii., 1875, 882: Simoglossus niger Chaudoir, Rev. & 

 Mag. Zool., 1872, 217; Col. Nov., 1883, 17. 



I have no doubt but that I am right in considering this 

 narrow, black species as ^Enigma unicolor; it is also evident, 

 from Thomson's description, that Castelnau identified Helluo- 

 niori)lia batesi rightly; but how Castelnau, Chaudoir, and 

 Gestro mistook Hope's species for one, the size of which was 

 20x6 mm. (the dimensions given by Gestro for Gigadema 

 minutum Cast., which these three authors thought probably 

 identical with ^E . unicolor Hope), surprises me, seeing that 

 Hope gives the size of his species as "Long. 7, lat.lilin." 

 Chaudoir, in the " Coleopterorum Novitates," says that he had 

 received his Simoglossus niger from Mr. William Macleay 

 under the name of Helluosoma atruni Cast. ; and that is the 

 name that Sir W. Macleay applied to H. unicolor Hope, in his 

 Collection. The generic diagnosis given above is sufficient for 

 the identification of H. batesi. Dimensions: length, 13'5; proth., 

 2-5 X 2-75, el., 6-5 x 3-3 mm. 



Hob. — Eastern Coastal Districts, from Clarence River to 

 Cooktown. 



