Malacoderm Genera Prionocerus and Idgia, 359 
contiguous (narrowly separated in ¢ ); anterior tarsal joints 
1-3 with a comb along their inner edge. Genital armature: 
lateral lobes narrowed and sinuously curved towards the 
apex ; median lobe broad, gradually narrowed, slightly 
hooked at the tip beneath. 
Hab. Sumarra, Padang [type], Sungei Kumbang, Siolak 
Daras, and Barong Bharu in Korinchi, alt. 3100-4500 ft. 
(Rodinson- Kloss Expedition : iv. 1914). 
Eleven specimens (5 ¢ ¢,6 2 2?) obtained by the above- 
mentioned Sumatran expedition are perhaps referable to 
I. longissima, Pic, type from Padang. Three only of them 
(2 2), with a relatively shorter apical joint to the antenne, 
have the legs wholly testaceous as described by the author, 
the others (¢ 9) having these limbs in part or almost 
entirely, as well as the head in front and the antenne 
(except at the tip), infuscate or black. The greatly elon- 
gated eleventh antennal joint is one of the characters given 
to separate J. longissima from similarly coloured forms 
(testaceous, with black head and violaceous apex to elytra) 
inhabiting the same regions. In the series before me the 
apical patch varies in development, from about one-eighth to 
nearly one-half the elytral length. To judge from Pic’s 
table (1910) of the testaceous Javan and Sumatran repre- 
sentatives of the genus, J. longipennis and I. longissima may 
be based upon the two sexes of one variable insect. Un- 
fortunately, the 2 only of the form with pale legs and 
antenne, with shorter apical antennal joint, is at present 
available for examination. 
43. Idgia cyanura, sp. 0. 
?. Elongate, widened posteriorly, shining, the elytra 
dull ; finely pubescent and sparsely nigro-setose ; testaceous, 
the head, antennee (except the basal joints and the tip of 
11), legs (the bases of the femora and the claws excepted), 
and a space down the middle of the ventral segments black, 
the elytra with a large nigro-cyaneous patch at the apex. 
Head small, the labrum strongly transverse, hcllowed in the 
middle in front, appearing subarcuate; eyes large, well 
separated ; antenne slender, rather short, slightly widened 
outwards, joints 7-10 decreasing in length, 10 subserrate, 
11 twice as long as 10, deeply excavate within. Prothorax 
wider than the head, not longer than broad, feebly sinuate 
at the sides. Elytra long, rather broad, widened posteriorly ; 
densely, rugulosely punctate, without granules on the disc, 
Length (excl. head) 83, breadth 3 mm. 
24* 
