rsrcjii:. 



[July — Aus">> i^^.v 



comlensetl." llagcti lurthcr .says "To a 

 certain extent the dermal colors may 

 have been derived fnjm livpodermal 

 colors, as the cuticula is secreted by tlie 

 hvpodermis, and the colors may have 

 been changed liv oxidation and air-tight 

 seclusion." Like organic colors in 

 general, I liave found dermal as well as 

 hypodermal colors to be subject to the 

 chlorin bleaching processes, which 1 

 first applied, in 1875, for the purpose 

 of studying the venation of lepido- 

 ptera,^^"'"' the onh' difference being this, 

 that dermal colors require to be freed, 

 bv long maceration, from tlieir prison 

 in the chitin. 



Broken scales become colorles 

 again .... 



but 



reor;un or 



Thus a distinction between dermal 

 and hvpodermal colors is that the 

 former bleach only by destruction of 

 tlie parts in whicli they are enclosed, 

 the latter bleach readily. I do not wish 

 to enter here into a prolonged discussion 

 of the chemical reactions vvliich are 

 similar or alike in dermal and hypoder- 

 mal colors, which I hope to discuss 

 later, after more experiments, but will 

 add a table which I think will serve for 

 the separation, imder the microscope, 

 of the different kinds of coloration, 



Bv this and other modes of sepai'ation 

 I have studied all tlie scales of coleo- 

 ptera which I had at mv command, and 



iginal coloration it" driucl 



The color remains until 

 the scales bejj^in to ma. 

 cerate and lose their 

 structural peculiarities .> 



Scales become more 

 transparent (if injured), 

 but retain some colora- 

 tion. .\dd to the wet 

 scales some chlorin-'^ 

 bleaching" solution and 



Washed with alcohol and 

 redried all the undestroyed 

 scales return to their original 

 coloration. ..... 



Reflected lig^ht shows 

 colors complementarv 

 to the orif^inal colora- 

 tion .... 



()/./,,,./ 



f- I 



Or\ 



Reflected li^ht shows 

 same coloration as trans- 

 mitted litfht . 



; Dermal 



I coloration. 



Washing with alcohol anil 

 redrying causes no further 

 change of coloration. 



The lolor disappears, in al most an hour or two, and ( llyfud.rmal 

 does not reappear by any subsequent treatment . . ^ coloration. 



I have only found optical and dermal of lepidoptera. optica! coloration, ex- 



(ne\ er hypodermal) coloration ; optical cept where concealed or subchied by 



coloration being common. In the case hypodermal coloration, is somewhat 



MDimmock, G. Bleaching the wings of lepidn. rare, and 1 have ne\er discovered scales 



ptera. (Psyche, Sept. 1S75, v. i, p. 97.99.) I 1 1 i ■ 1 



■lODimmock, G. A method of bleaching wings of ""'•'i'^ (lemial coloiatiou Occurred. 



lepidoptera, to facilitate the study of their venation. ('rins ya-w ocriir in lirilll-mt o-iilH 

 (Proc. Amer. assoc. advanc.sci.,iS7S,v.24.p.22S-230.) V ' "'S ni.iy oct-Ul m inuil.mt golll 



