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IX. Notes on Dyscrltlna longisetosa, Westvv. By 

 E. Ernest Green, F.E.S. 



[Read March 18th, 1896.] 



The accompanying figures represent what I suppose to 

 be a more advanced stage of the interesting little insect 

 described by the late Prof. Westwood, under the name of 

 Dyscritina longisetosa (Trans. Ent. Soc. Lond., 1881, 

 p. 601, pi. xxii., fig. 1). 



My example of the insect is rather darker coloured 

 than the type, the whole of the upper parts being dark 

 reddish-brown, without any pale bands on the abdomen ; 

 it has, however, the two small pale patches on the 

 posterior angles of the prothorax ; and there is a pale 

 median line bisecting each of the thoracic tergites longi- 

 tudinally, which is carried forwards to the middle of the 

 head, where it bifurcates, the branches turning sharply 

 off to a point on the margin immediately in front of the 

 eyes. 



Westwood does not definitely state the dimensions of 

 his insect ; but gives 8 lines as the length of the caudal 

 filaments, remarking that these are " nearly three times 

 the length of the entire insect." In his figure, however, 

 he gives a scale, indicating the lengths of the parts, by 

 which I find that the body is 6 mm. long, and each 

 filament 17 mm. In my specimen these proportions are 

 considerably altered, the body being 8 mm. long, while 

 the caudal appendages attain a length of only 6,^ mm. 



In Westwood's description these caudal appendages 

 are said to be composed of more than fifty minute articu- 

 lations. In the present specimen, the two appendages, 

 though nearly of equal length, consist of a different 

 number of joints, there being seventeen in one and twelve 

 only in the other. I at first thought that they might be 

 imperfect ; but a careful examination of the extremities 

 shows a natural rounded termination quite unlike the 

 apices of the preceding joints. There is a very long basal 

 joint, about equal to the subsequent six ; the remaining 



TRANS. ENT. SOC. LOND. 1896. — PART IT. (jUNE.) 



