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BIOLOGICAL NOTES ON ORIENTAL HEMIPTERA, No. 1. 



BY 



J. (!. Kershaw and G. W. Kirkaldy. * 

 (With a Plate.) 



This, the first of a proposed series of biological notes on Oriental Hemiptera 

 illustrates the metamorphoses of two widely distributed forms, viz., Dindymus 

 sanguineus and Caenocoris marginatus. 



1. Dindymus sanguineus (Fabr.) 

 PL figs, la — 5a and text figs. 1 — 4. 



This belongs to the Family Pyrrhocoridse, and is distributed from India and 

 Ceylon to China. The examples now described were bred up from eggs taken 

 in Macao. The metamorphoses of Pyrrhocoris apterus and of some species of 

 Dysdercus are partly known, but not of any species of Dindymus. 



A pair was taken in cop. on February 16th, 1907, in the evening and 

 remained in that position till noon of March 2nd, when they separated and 

 began to feed on house-flies. The female, with enormously distended 

 abdomen, laid a batch of 30-40 egg? in a heap on the floor of the cage (though 

 fresh vegetation was always kept in it) on the evening of March 5th. 



The ova are elongate oval, without a special cap, very pale yellowish. 

 (PI. fig. la). They hatched on March 30th. 



The first nymphal instar is pale orange with red eyes (fig. 2a) ; the labium 

 (rostrum) on the first day reached only a little way beyond the thorax. A 

 moult occurred on April 4th ; the second instar is dark orange -coloured, with 

 little change in form. The third instar hatched on April 8th, blood-red, 

 shining, head, thorax, &c., reddish brown, antennae and legs brown. The fourth 

 instar hatched April 13th, and is very similar to the preceding, but 

 has the fourth segment of the antennae whitish at the base. These young 

 nymphs are very fond of Termites and suck them in preference to anything 

 else. The fifth instar hatched on April 28th (PL fig. 3a), followed by the sixth 

 instar on May 7th; but there was little change, except in size. The seventh 

 instar hatched on May 14th, followed by the eighth on the 25th. In the latter 

 the tegminal pads are well developed, reddish, as also the pronotum : head and 

 abdomen apically blackish ; eyes dark red. Abdomen basally greenish. Pleu- 

 rites chequered red and yellowish (PL fig. 4a). 



In the first instar the odoriferous orifices are very minute, orange coloured. 

 In the third they are blackish and remain so till the last. (The nymphs then 

 died.) 



Such a large number of moults in a Heteropteron is unprecedented and 

 requires wider investigation. For the present, they may be grouped as 

 follows : - (*) (fu). An Ethiopian Cimicid, Bathycoelia thalassina. has been 



* The credit for the major part of this paper is due to Mr. Kershaw. I have merely 

 identified the material and arranged the letter press, occasionally adding a few details. 

 -G. W. K. 



