37 



procured for me a perfect specimen of the insect, and assisted me in 

 mounting numerous scales, taken from various parts of the wings, an 

 opportunity was afforded me of extending the inquiry, and I was in- 

 duced to draw up the present communication, under the impression 

 that the result of the investigation might have some interest for the 

 members of the Society. 



I may premise that the insect, from which the scales were obtained, 

 is the male Amathusia Horsfieldii (Kollar) or the Amathusia Inachus 

 (Boisduval), it is represented at Plate VIII. fig. 8 ; the colour of the 

 upper surface is a deep brown, of velvety aspect, besprinkled with 

 blue near the shoulders, the upper wing being marked with a broad 

 orange band, and two small white spots. The under surface of the 

 wings is of a pale brown, richly marked with a darker brown. 



The scales of the Amathusia Horsfteldii vary considerably in size, 

 shape, and in the distance and character of their markings, even 

 when taken from the same part of the wing. In Plate VIII. are de- 

 lineated some of the more remarkable scales, as seen when magnified 

 two hundred and ten diameters ; a dozen plates, however, would not 

 contain all the varieties. Figs. 1, 3 and 4, represent scales from the 

 under side of the upper wing near the shoulder. In fig. 1, the longi- 

 tudinal strise are a ten-thousand-two-hundred-and-fiftieth of an inch 

 distant, and tolerably regular, the transverse strise being as close as 

 from a thirty-thousandth to a twenty-thousandth of an inch ; the 

 latter when magnified eight hundred diameters, split into very dis- 

 tinct dots. The longitudinal and cross striae of the scale (fig. 3) 

 are about a ten-thousandth of an inch apart, the markings having 

 the character of those represented in the large drawing, Plate IX. 

 In the scale (fig. 4) the longitudinal strise are a twenty-thousandth of 

 an inch apart, and the cross striae a thirty-five-thousandth of an inch. 



Figs. 5 and 6, represent that modification of the scale which con- 

 stitutes the hair, and fig. 7 a narrow scale, of a structure approxi- 

 mating to that of the hair ; these were taken from the top side of the 

 under wing, near the body. Neither cross nor longitudinal striae can 

 be made out with distinctness, though the same structure is seen to 

 exist, but so much compressed, as to render its definition difficult ; 

 the hair was measured and found to be the three -thousand- seven- 

 hundred-and-fiftieth of an inch broad. 



Figs. 9, 10 and 13, are from the under side of the tip of the upper 

 wing. In fig. 9, which is one of the scales possessing the peculiar 

 markings, the longitudinal striae are from a ten-thousandth to a six- 

 thousand- eight-hundredth and a five -thousandth of an inch apart, the 



