274 



CICIKDELIDJi. 



developed, acute at apex ; labial palpi strongly developed, the 

 basal joint large and broad, the second longer and broader than 

 the first at the base, subtriangular, gradually narrowed to apex, 

 the third usually short ; the characters, however, of the palpi 

 appear to vary in different species ; pronotum more or less 

 parallel-sided, broad, constricted in front and behind, occasionally 

 slightly convergent but without a collum in front ; elytra narrowed 

 in front, dilated and very convex behind ; underside smooth and 

 shining, mesosternum long, episterna of mesosternum very narrow 

 and deeply sulcate ; legs very long. 



In both sexes the anterior, and in fact all the tarsi are more 

 or less pubescent or rather spongy pilose beneath, but the anterior 

 tarsi are more dilated in the male, and have the third joint very 

 strongly dilated on its inner side. The armature of the upper 

 margin of the last ventral segment is much the same as in Collyris, 

 but the two central projections on the under margin, so charac- 

 teristic of the latter genus, are wanting in Tricondyla, the centre 

 of the margin being often more or less emarginate. 



The species, as will be seen from the figures, much resemble 

 large ants, but it appears to be open to doubt whether the resem- 

 blance is in any way significant, and not rather accidental : the 

 likeness between Tricondyla a/ptera, 01., and the large ant, Cam- 

 jionotus [jigas (called by the natives sennit gajcih or " elephant 

 ant"), which occur together in the Malay region, has been espe- 

 cially noticed by Mr. liidley, and may be a case of true mimicry. 

 This is noticed by Mr. Eobinson in the ' Fasciculi Malayenses, 7 

 Zoology, pt. i. October 1903, p. 179, &c, from which we have 

 already quoted an instance of mimicry bearing both on Collyris 

 and Tricondyla (supra, p. 220) ; it may, however, be of interest 

 to quote another instance from the same work bearing on Tri- 

 condyla alone. In speaking of T. altera (I. c. p. 180) he says : — 

 "I took two specimens of this species running about together 

 on sand at the foot of a tall tree in open country. Their resem- 

 blance to a fossorial wasp (Spliex lobatus, I\), common in the same 

 environment, was so marked that the Malays with me begged me 

 not to touch them, remarking that wasps of that kind stung very 

 badly. The wasp is seen frequently running about on sand, with 

 its wings folded in such a way as to be very inconspicuous, but at 

 the same time to somewhat veil the brilliant iridescent blue of the 

 abdomen. It never runs straight for any distance, being probably 

 employed in hunting other insects, perhaps 'ant-lions,' in the 

 sand, but frequently stops for a moment and then resumes 

 motion in another direction. The beetle had exactly the same 

 gait and movements, and its resemblance to the wasp was due to 

 this rather than to any very detailed similarity of form or colour, 

 though in these respects, too, there is a general likeness even in 

 the set specimens. In the present instance it would seem that the 

 beetle mimicked the wasp, rather than the wasp the beetle, the 

 wasp being by far the commoner of the two insects, and also 

 the more noxious. The bearing of Mr. Ridley's observation (with 



