38 



Among some Arizona material recently examined we have dis- 

 covered several species very closely related to the above, one of which 

 we have identified as iiitcralbicalis Rag. the type of the genus Macro- 

 theca. A comparison of the generic definitions of Macrotheca Rag. 

 and Cacotlicral>hi Dyar has convinced us that they are synonymous, 

 the former holding ; this conclusion is borne out by the material before 

 us, nigrocincrcella and mtcralbicaUs being identical in venation, palpal 

 structure, etc. Ragonot had but a single $ specimen before him at 

 the tiine and was unaware that in the 9 sex, which we have before us, 

 the palpi are long, slightly bent downward and smoothly scaled, cor- 

 responding in this respect to those of the genus Alpheias Rag. The 

 S 's of the above species possess very short, tufted palpi, which 

 at first gave us the impression that they had been partially broken off. 

 An examination under the microscope of the denuded organ showed 

 a most extraordinary and abnormal development ; the basal joint con- 

 sisted of a narrow ring, the second joint was much swollen basally, 

 the dorsal portion being drawn out to a point, whilst the third joint 

 had become more or less atrophied and projected inward at right angles 

 to the second joint, interlocking with the corresponding joint of the 

 adjoining palpus (Plate IV, fig. 5). The dorsal portion of the second 

 joint in a natural state being thickly tufted, the whole presents a most 

 indefinite appearance at first examination. 



The species flcxUincalis proves on examination to be congeneric 

 with iiitcralbicalis and iiigi-ocincrcclla; poiida, however, has veins 8 

 and 9 stalked from 7 and would fall according to venation in Alpheias 

 Rag. As the $ 's and 9 's of this species present the same peculiar 

 diflferences in palpal structure which we have already noted and 

 as Ragonot's genus Alpheias was founded on 3 9 's belonging 

 to two species and his genus Amestria on 2 S 's, and as furthermore 

 the venation of both genera is said to be identical, we have very little 

 doubt, even without an actual knowledge of Ragonot's species, but 

 that the distinction between the two genera is merely a secondary sex- 

 ual one and that Amestria Rag. will become a synonym of Alpheias 

 Rag. Ragonot has evidently mistaken the tufts on the dorsal portions 

 of the second joints of the laljial palpi in the 6 for the maxillary palpi 

 which he states to be "tres epais et squammeux" ; as a matter of fact 

 they are lacking. For two other related s])ecies, both of which are ap- 

 parently new, we have created new genera, which we characterize 

 later. 



