Royal Mierosco]}ical Society. 247 



II. — RemarJcs on the General and Particular Construction of the 

 Scales of some of the Leindoptera, as hearing on the Structure 

 of the " Test Scale " of Lejjidocyrtus curvicollis. By E. L. 

 Maddox, M.D. 



(Bead before the Royal Microscopical Society, 3Imj 3, 1871.) 

 The investigation of the intimate structure of some minute objects 

 with which the microscopist is quite famihar, whether for the pur- 

 pose of demonstrating their integral beauty and exquisite design, or 

 for exhibiting and testing the optician's skill, is a source so replete 

 with difficulty, that the opinions of trustworthy observers are pre- 



EXPLANATION OF PLATES LXXXVI., LXXXVIL, and LXXXVIII. 



Lcpidoptem Scales and Fragments. 



Fig. 1. — Part of a China butterfly scale — Tanonia CEnoiie, Ind. China — showing 

 the outer transjjarent membrane : to the left, a beaded appearance of 

 the framework, out of focus ; to the right, various chromatic eflects in- 

 duced by change of focus and direction of the incident light. X 1600. 



„ 2. — The same portion of the scale, showing the structural framework of the 

 ribs and transverse bars, x IGOO. 



„ 3. — Part of the same scale seen reversed, indicating on the ribs what is 

 believed to be the vertical attachments to the outer or middle mem- 

 brane when three exist, x ICOO. 



„ 4. — Part of another scale of the same insect, showing the outer membrane 

 and the framework with chromatic interference and pseudo-beading, 

 X IGOO. 



,, 5. — Part of a large yellowish-white scale from a China butterfly wing — 

 Fajjilio Eritlwnius (Cram.), Ind. China. At one side is seen the violent 

 chromatic effect of interference caused by the longitudinal ribs and 

 oblique attachments — " striaj " ; also the markings of the transverse 

 bars on the (middle or?) outer membrane, for it appears to consist of 

 two layers. X 1000. 



„ 6. — An injured dark scale from P. Erithonius (Cram.), Ind. China, with 

 a portion of the inner pigmentary membrane turned over, and the 

 middle showing the vertical attachments of the ribs, and the outer 

 membrane, X 1000. 



„ 7. — An injured dull-grey scale from the same butterfly, indicating the inner 

 ribbed membrane with its pale, granular, pigmentary deposit, and 

 the oblique framing of the middle or outer layer (" strias"), x 1000. 



„ 8.— Irregular fragments of the external pigmentary deposit from a dark scale 

 of P. Erithonius, X 1000. 



,, 9. — Part of a scale from the wing of the same butterfly as Fig. 1, showing 

 three membranes — the outer, the middle retaining a part of the frame- 

 work, and the inner with the heavier portion : also two fragments ; 

 outer membrane, a; ribs, b. x 950. 



„ 10. — Fragment of a foreign butterfly scale, received from Mr, JVIcIntire (upper 

 surface of wing and scale), showing the membrane and delicate frame- 

 work, with indications of a beaded appearance due to thickening at the 

 junctions of the bars and ribs, x 1600. 



,, 11. — Fragment of a scale from the same insect, showing a marked pseudo- 

 beaded appearance in the ribs. The scale is remarkably free of pig- 

 ment. X 1600. 



,, 12. — Pait of a scale from the same butterfly (under surface of wing, upper 

 surface of scale). The transverse bars are rare, except at the edge ; 

 the longitudinal ribs, which show the sujjposed vertical attachments 

 at one or both sides of several, producing when in place the pseudo- 

 beaded appearance, well seen in the rib. x 1600. [Fig. 13. 



T 2 



