Char acter istik der Gattungen der Notacanthen. 379 



constant in the Leptidae, than in the Xjlophagidae, Strationiyidae etc." 

 (Compare Burgess on Glutops in the Proc. Boston Soc. N. H. 1878, 

 p. 321.) — In my Catalogue, I left Arthropeas in the place which 

 Loew had assigned to it, because I did not feel prepared to introduce 

 the reform I am proposing now. And thus an inconsistency arose with 

 regard to Glutops, which I placed at the end of the Leptidae, quite 

 far from Arthropeas. 



III. Latreille, in defining his Xylophagus, had principally Subula, 

 and especially S. macidata in view; he figures it, and mentious its 

 habits (Genera Crust. et Ins. IV, p. 272; Tab. XVI, f. 9, 10). The 

 true Xylophagi he had either not studied attentively, or, still more 

 probably he may have known them from descriptions and figures only. 

 A close scrutiny of Latreille's wording is, in this respect, convincing. 

 Compare, 1. c, the defination of his Xylophagus: Antennae ad 

 apicem attenuato-acuminatae etc. agrees with Subula maculata, and 

 not with Xylophagus, not even with Subula varia. — Palpi articulo 

 primo manifesto crassiore; cellula stigmosa non fuscata; 

 both characters are not applicable to our Xylophagus. The only reference 

 to the true Xylophagus I find in the description of the venation, because 

 here he had figures to compare. In speaking of the posterior cells, 

 he says imperfectae, aut illarum tertia solum, -XyZ. macidatus, 

 couclusa. In quoting the figures of Xylophagus cinctus, especially 

 S chellenberg's he is very naturally Struck by its resemblance to his 

 Pachystomus (ßhagio) syrphoides Panzer (,,Rhagioni syrphoides dorn. 

 Panzer prima fronte, simillimus!"). He would certainly not have spoken 

 in that way of a figure, if he had had a specimen to compare; and in 

 such a case it would not have eseaped his keen eye that his Pachy- 

 stomus is nothing but a Xylophagus with brooken antennae! 



Observe that in the Genera (1809) Latreille places Pachystomus 

 among the Leptidae; in the Familles naturelles he forms for Pachy- 

 stomus and Coenomyia the family Sicarii, which he places near the 

 Leptidae; äud this is the exactly the arrangement which I am proposing 

 to restore. 



IV. I would not express a final opinion on the other genera of 

 doubtful Position belonging to the same groups, without again having 

 examined specimens; they are beyond my reach at present. What I 

 have to say now is merely based on recollections. 



Heterostomus, Bhachicerus, Electra, Chrysothemis will probably 

 remain among the Xylophagidae. 



XXVI. Heft II, 25 



