THE ARMATURE OF INSECTS 



187 



Verhoeff, C. Beitrage zur vergleichenden Morphologie des Abdomens der 

 Coccinelliden, etc. (Archiv f. Naturg., Ixi, pp. 1-80, 6 figs., 1895.) 



Boas, J. E. V. Orgaue copulateur et accouplement der hanneton. (Oversigt 

 over det K. Danske Vidensk. Selskab Forhand, 1892, Copenhagen, 1893, 



1 PI., pp. 239-261.) 



Perez, J. De Porgane copulateur male des Hyme'nopteres et de sa valeur taxo- 

 nomique. (Ann. Soc. Eat. France, Ixiii, pp. 74-81, Figs., 1894.) 



Goddard, Martha Freeman. On the second abdominal segment in a few Libel- 

 lulidte. (Proc. Amer. Philos. Soc., xxxv, pp. 205-212, January 11, 18U7, 



2 Pis.) 



Also the writings of Eaton, Emery, Fischer, Forel, Ge"hin, Godart, Ilagen, Joly, 

 Koletani, Loew, Meinert, Mik, Nicolet, Osten Sacken, Pictet, Koussel, 

 Schaeffer (1754), Schaum, Schenk, J. B. Smith, Thompson, Buchanan- 

 White, Brunner von Wattle -Wyll, Weise, Wyenbergh. 



The subject of copulation has been treated by Hoffer, Hartig, Schiedeknecht, 

 Verhoeff, Stitz. 



FIG. 208. Lirva of Dryocampa rubicunda, stage 

 II. Bridgham del. 



THE ARMATURE OF INSECTS: SET^, HAIRS, SCALES, 

 TUBERCLES, ETC. 



The cuticula. The integument is externally either smooth and 

 shining or variously punctured, granulated, tubereulated, striated, 

 or hairy. In certain orders 

 the skin is clothed with 

 flattened setae or scales, 

 while many forms, as some 

 caterpillars (Figs. 208, 209), 

 beetles (Fig. 210), etc., are 

 protected by spines, horns, 

 etc., these in adult insects 

 often forming secondary 

 sexual characters, usually being more developed in the males than 

 in the females. 



The cuticula is not always smooth, but is often finely granulated or even 

 minutely spinulated. On the abdominal segments of Anabrus, as observed by 



Minot, the cuticula is armed with 

 microscopic conical nodules scattered 

 irregularly over it. They do not 

 correspond, he says, in any way to 

 hairs ; for they do not rest over 

 pores, nor did he see any specially 

 modified cells underlying them. " As 

 far as I have observed, they are mere 

 local irregularities, each nodule being 



ic. 209. -Larva of Hyperchiria io, on hatch- a pp are ntly supported by some four 



or six unmodified epidermal cells." 



Minot adds that the whole of the cuticula, except the cones just described 

 and the hairs, is divided into numerous minute fields, each of which cor- 



