84 



Thessalia Scud. 1875. 

 Type specified as leanira Feld. 



EUPHYDRYAS SCUD. 1872. 



Type specified as phaeton Drury. 



Having established the available genera and their types we have 

 examined the $ genitalia of cinxia and phoebe, the two European spe- 

 cies which are the respective types of Melitaea Fabr. and Cinclidia 

 Hbn. We have further examined the genitalia of practically all our 

 N. American species and find that they may be divided very readily by 

 this means into two main groups, the first group including phaeton, 

 chalcedona and all the species listed in Dyar's catalog under Lemonias 

 as far as helvia (No. 160) and the second the remainder of the species 

 included in the same list under Lemonias, Cinclidia, Thessalia, and 

 Schoenis. The first group, which also would include the European 

 matnrna and probably allied species which we have not examined, 

 shows a marked similarity in pattern among the included species and 

 would admirably bear out the conclusions of Mr. Bethune Baker in 

 a recent paper (Ent. Record, XXVI, 177, 1914) where he claims that 

 a correlation of structure and pattern is to be met with all through the 

 Rhopalocera; for this group the only generic name available seems to 

 be Euphydryas Scud, which we propose using. We have not extended 

 our studies further than the genitalia but imagine other structural 

 characters may be found bearing out the above results. With re- 

 gard to the second group the genitalia show considerable affinity to 

 those of the European phoebe and cinxia; it is true that the genitalia 

 of cinxia vary from those of phoebe in the form of the claspers but 

 the general type is the same and we would not for the present separate 

 these two species into different genera. Our N. American species, es- 

 pecially in the palla group, show distinctly a further development of 

 the phoebe type ; we think therefore that the genus Melitaea Fabr. may 

 safely be used for all the members of this group; neither harrisi nor 

 leanira, the types respectively of the genera Limnaecia Scud, and 

 Thessalia Scud., shows any peculiarity which would warrant a separa- 

 tion either from each other or from the remainder of the species, and 

 these two genera would therefore fall. If it be considered necessary, 

 after further study, to separate our N. American forms from the Euro- 

 pean the genus Limnaecia Scud, would still be available. In the minuta 

 group we find the greatest points of difference from the general type 



