ANTENNAE OF LEPIDOPTERA. 35 



in degree to make the use of this character practicable in taxononiic 

 work. The hexagonal form is characteristic of the Pyralidina, see 

 Fig. 34. Among the Tortricina the lengthening process has begun, 

 and the foi-m shown in Fig. 35 is characteristic. Even where little 

 elongation has taken place, the areas are much more irregular, and 

 many of them have sharp angles in their outlines, which are not 

 found among the Pyralidina. In the Tineina the i)rocess has been 

 carried much farther and the form shown in Fig. 3() is characteristic. 

 So far as I have examined, none of the Pyralidina has areas of the 

 second or third form ; none of the Tortricina has areas of the third 

 form. The only liability of error in the use of this as a recognition 

 character is due to the fact that in a few forms a heavy coating of 

 scales has I'etarded the progress of the development, and we may 

 find a Tortricid with a surface like a Pyralid, or possibly a Tiueid 

 with a surface like a Tortricid or a Pyralid. These cases, however, 

 are rare, and where they do occur, there is usually some other char- 

 acter, such as the long, clavate scape so common among the Tineids, 

 which will make it possible to separate the forms. There are many 

 variations in the antennse of the Microfrenatpe. The peculiar modifi- 

 cation of segments and scales near the middle of the clavola of the 

 male Desmia fiineralis, Fig. 29, the crest of scales along the base of 

 the clavola of the male Laodamia fusca, and of certain of the Tineids, 

 the strange, tufted, membranous expansion of the scape among the 

 Epipaschiinse, Fig. 28, are examples of some of these variations, but 

 the main structural characters remain the same even in these forms. 



Thei'e are a few points of structure in connection with some of the 

 families of this group which are worthy of mention. Among the 

 Cranibidse, the ventral expansion is greater than in the other iami- 

 lies. It reaches an extreme in Cramhus mutabilis. Fig. 21, and re- 

 sembles the form so common among the Sphingidre. The antenna; 

 of the Pterophoridie and the Orneodidie show a wide difi'erence in 

 their structure. Those of the former family are distinctly of the 

 Pyralid type, while the latter are just as distinctly of the Tineid 

 type. I believe a further study of the characters of other organs 

 will prove the Orneodidte to be more closely related to the Tineids 

 than to either the Pyralids or the Tortricids. The surface marking 

 is Tineid in form, and the scape has the long and slightly clavate 

 shape so common among the Tineids. 



The antennre of the Sesiidte, which we have excepted from the 

 statements made of the Microfrenata;, are distinctly diflferent in 



TRANS. AM. KNT. SOC. XXIII. FEBRUARY, 1896 



