236 MR. R. SnELFORD OX MIMETIC IXSBCTS AXD [Xov. 4, 



belonging to the most diverse orders, such as Hemiptera, Diptera, 

 Lepidoptera, and Coleoptera. 



The model is one of those reddish-ochraceous Braconids, of 

 which there are many representatives in Borneo, all being more 

 or less common. This particular species, with a conspicuous black 

 stigma on the fore wing, is eminently a mountain form, as the 

 numerous specimens in the Sarawak Miiseum bear witness. 

 Mt. Matang at any elevation above 1500 feet is its favourite 

 haunt, but I have never taken it below that altitude. The mimic, 

 which was recently described ^ by Mr. McLachlan, was captured 

 in the month of August also on Mt. Matang, at an altitude of 

 2500-2800 feet. It, too, is reddish-ochraceous, whilst each wing 

 bears a black stigma, those on the fore- wings being slightly more 

 conspicuous than those on the hind- wings ; the sides and ventral 

 surface of the abdomen are pure white (in the fresh condition), so 

 that when the insect is seen in profile its somewhat bulky body 

 appeal's to be reduced approximately to the size of the body of 

 its model ; as, further, the model also has the ventral surface 

 of the abdomen coloured white, the resemblance between the two 

 insects is still greater (compare Plate XIX. figs. 22 & 23). This 

 method of producing a thin- bodied or w-asp-waisted effect by white 

 patches is by no means uncommon amongst insects ; I shall be 

 able to give further examples of it in this paper [vide infra, 

 pp. 238, 241), and at present need only refer to the well-known 

 Soudanese Locustid Myrmecojyhana fallax (Br.) mimicking an ant, 

 and to the Moth Fseudosphex hycdina which mimics a Sphex. 



ii. Mimic. Mantis'pa sp. Plate XIX. fig. 27. 



Model. Polistes Sagittarius (Sauss.). Plate XIX. fig. 26. 



The Wasp, P. Sagittarius, is an extremely common species and 

 is rendered highly conspicuous by reason of a red band on the 

 second abdominal segment ; the rest of the body is black, varied 

 on the head and thorax with a rich red-brown ; the wings are 

 fuscous, becoming flavo-hyaline outwardly. The mimic is black 

 with the second and third abdominal segments red, the width of 

 these two segments closely corresponding with the large second 

 abdominal segment of the wasp ; the wings are hyaline, but largely 

 shaded with fuscous at the base and along the costal margins and 

 flavo-hyaline at the apex (compare figs. 26 & 27). A closely allied 

 species from Assam is in the Hope Collection at Oxford, with the 

 MS. name of M. nodosa (Westw.). The sjDecimen belonged to the 

 Cantor Collection. 



iii. Mimic. Mantispa sp. Plate XIX. fig. 25. 



Model. Polistes sp. near diaholicus (Sauss.). Plate XIX. fig. 24. 



The general colour of the Wasp is reddish-brown, the abdomen 

 is covered with a fine silky pubescence golden in colour ; this 



1 Ent. Month. Mag. (.■^er. 2) vol. xi. 1900, pp. 127-128. 



