444 On the Melolonthine Beetles of Ceylon. 
Microtrichia in Brenske’s table are incorrect, the following 
one may be substituted :— 
1 (2). Elytra not setose.......... $b ae 94 4 stnghalensis, Brenske. 
2 (1). Elytra setose. 
3 (4). Body clothed with soft hair beneath .... furcifer, Arrow. 
4 (3). Body without soft hair. 
2 (6). Upper surface slightly shining .......... eurystoma, Burm. 
6 (5). Upper surface not shining, very densely 
punietured’), 1.15. FIs kt ease Pela nists Sets costata, Walk. 
IDIOCHELYNA, gen. nov. 
Corpus elongatum, paulo depressam. Pedes modice longi; tarsi 
parum graciles, quam tibias vix longiores; ungues simplices. 
Antenne 8-articulate, clava 5-articulata, elongata. Clypeus 
angustus, subcircularis, basi leviter constricto, margine fortiter 
reflexo. Labrum acuminatum, ad clypeum connatum. Man- 
dibule obsoletze. Maxille degenerate, palpis gracilibus, 4-articu- 
latis, articulo ultimo longo. Labium parvum, digitiforme, palpis 
contiguis, biarticulatis, articulo ultimo longissimo, recto. Abdo- 
men subtus haud solidum, paulo arcuatum. 
Femina igunota. 
This genus is constituted for ‘‘ Zsonychus”’ pectoralis of 
Walker, a very peculiar insect without near affinity to any 
known Oriental genus. It belongs to the curious group in 
which the biting-parts of the mouth have completely degene- 
rated, and the nearest related forms known to me are Pachy- 
colus and Perissosoma, of the Madagascar region. As is the 
case with those, only the male is known. ‘The legs are 
fairly long, but the tarsi are scarcely longer than the tibiz 
and the claws are quite simple. ‘The antennz consist of only 
eizht joints, the three basal ones short and stout, and the 
remaining five forming a long club to which the footstalk 
is attached at about a third of its length. Mandibles are 
practically absent, and the maxille merely form bases 
tor the long straight palpi, of which the last joint is 
as long as the other three together. The labium forms a 
long finger- like process, with “its palpi close together and 
consisting of a short basal joint and a terminal one about 
four times as long. 
Several specimens of this were taken by Mr. E. E. Green 
at Hakgala in September. 
