MORGAN HEBARD 



The Styles, present only on the male subgenital plate, have often 

 generic or even higher significance in their general character, 

 though in some genera very distinctive types are found, which 

 are clearly of specific diagnostic value alone. ^^ In many species 

 slight but constant differences in the styles are found. It appears 

 that often when the male concealed genitalia are highly specialized, 

 the styles remain simple in structure; while when the male con- 

 cealed genitalia are more simple, the styles often become highly 

 specialized. The high specialization in these two sets of organs 

 apparently shows in different forms, at least in part, an analogous 

 function. In other groups both concealed genitalia and styles are 

 more simple in structure. In some species no styles are found on 

 the male subgenital plate. 



The limbs themselves show few readily describable diagnostic 

 features, but their general character of armament is apparently 

 of the highest value in the arrangement of the groups and also in 

 separating many genera. Slight differences are, with few excep- 

 tions, worthless for specific separation. The limbs often differ 

 greatly in the sexes of species where general dissimilarity between 

 males and females occurs, this even extending to the limb arma- 

 ment in certain species. The presence or absence of pulvilli and 

 arolia are of value in associating the groups; rarely these organs 

 show, in their structure, features of specific diagnostic value. 



It must be remembered that, until the Blattidae of the world 

 are monographed, the relative values of all the diagnostic features 

 can not be fully determined. The above statements, however, 

 apply fully to the forms here treated and to the exotic material 

 examined. 



It is evident that, until such monographic work is accomplished, 

 the validity and proper position of some of the subfamilies will 

 remain in doubt. Thus we can not say whether the Ectobiinae 

 can be separated from the Pseudomopinac by sufficient characters, 

 or whether all of the genera there included are properly located. 

 In fact, exceptions, in different degree, to the majority of the sub- 

 family characters given by Shelford occur. That author had 



11 Note the great diversity of these appendages in the genus Cariblatta. See licbard, 

 Trans. Am. Ent. Soc., xlii, p. 153, (1916). 



MEM. AM. ENT. SOC, 2. 



