J6 SPOLIA ZEYLANK'A. 



DEUTEROCOPUS, Zeller. 



This interesting little genus, which was founded by Zeller in 1852 

 (Linn. Ent. VI., 402) for the reception of tengstrcemi, may at once 

 be recognized by the fact that the fore wing is split into three seg- 

 ments, the normal second segment being itself subdivided to about 

 half its length. (See Plate B., figure C.) 

 $0C Fisse "species" have been described: tengstrcemi, Z. ; ritsemce, 

 Sofrfc***",'kU£Wlsm. ; rubrodactylus , P ag. j^planeta, Meyr. ; famulus, Meyr. ; but 

 as a rule these little moths seem scarce in collections, and the specific 

 characters have therefore been taken from short series or even from 

 single specimens. Working in this way, it is easy enough to divide 

 up the available specimens into species or forms or races, but the 

 extraordinary amount of individual variation renders this grouping 

 useless when larger series of examples of this genus are being dealt 

 with. A few months ago I possessed seven specimens of Deutero- 

 copus from Ceylon, and these were clearly separable into four 

 " species" ; in June, 1908, I caught or bred 19 other examples from 

 Galle, and I have lately been able to see a specimen in the collection 

 of Mr. G. B. de Mowbray ; an examination of these 27 specimens 

 has convinced me that we have only one real " species " of this 

 genus in Ceylon. It is true that this species is divisible into four 

 forms, each with its distinct fades ; these I have shown in the table 

 and synopsis, but the differences shown in the table must be taken 

 as typical of the extremes of the various forms, and must certainly 

 not be considered as invariable. Indeed, there appear to be no 

 characters which do not vary from an appearance typical of one 

 form into that characteristic of any of the others; perhaps the 

 colour of the pectus and ventral surface of the abdomen may be 

 taken as a character as constant as any. 



My opinion of these forms is that all the Ceylon specimens belong 

 to one highly variable species which has already broken up into 

 several well-marked subspecific forms, still fused by syngamy into 

 a single species, and that these forms may be regarded as species 

 in the making, ready to break away from the parent stock by the 

 development of asyngamy through the effects of isolation or pro- 

 nounced preferential mating. Meanwhile, it is convenient to treat 

 the different forms as distinct for the purpose of identification of 

 their specimens by local collectors. ^ 



Since writing the above I have found D. tongotnom i abundantly 

 at Hambantota, and an examination of some sixty specimens of 

 this form shows that it is on the whole more constant within 

 certain limits of variation than appears to be the case in the other 

 three. In this case isolation, by the larval habit of feeding on a 

 plant typical of the very dry districts, seems to have separated off 

 this form from the other three characteristic of the wetter parts of 

 the Island, and I am now inclined to consider it a true species 



