184 C. R. Osten Sacken: 



great desideratum, as the determinatiou of the species, owing to their 

 multitude, is now becoming very difficult aud imcertain. Dr. Friedr. 

 Westhoff, in his important paper „Ueber den Bau des Hypopygiums 

 der Gattung Tipula Meig. Münster 1882" Jias given an outline of such 

 groups for the european species (1. c. p. 37 — 42), but he observes 

 with perfect reason that a work of that kind, in order to be satis- 

 factory, ought to embrace the species from all parts of the world. 

 Mr. Belings numerous descriptions of the larvae and pupae of Tipu- 

 lidae may furnish useful characters for the establishment of groups. 



I will notice here that Mr. Lioy in his work: I Ditteri distri- 

 buiti secondo un nuovo metodo naturale, Venezia 1864, p. 34 proposes 

 a new genus Anomaloptera for Tipula nigra; the only ground 

 given for its Separation from Tip^ila is that the second posterior 

 cell, in most specimens, is sessile, as in Paxhyrrliiha. In order to 

 distinguish Anomaloptera 'from PachyrrJiina, the generic definition 

 is put thus : „ Characters of Pachyrrhina , but the Prolongation of 

 the head rather long and narrow; front flat; first Joint of the an- 

 tennae elongate." At any rate the name Anomaloptera ispreoccu-, 

 pied twice (Coleoptera and Hemiptera). 



Pachyrrhina, although'a compact enough genus, contains some 

 forms of transition towards the genus Tipula, that require a closer 

 study than they have as yet received. 



Nephrotoma , based upon an abnormal number of joints of the 

 antennae (g 19, $ 15) can hardly be maintained as a genus sepa- 

 rated from Pachyrrhina. The number of .joints, as well as their 

 structure,- is variable in the latter genus. The north -american Pa- 

 chyrrhina eucera Loew, Centur. lY, 39 has the same number of 

 joints as the european Nephrotoma (19 g, 159). But the north- 

 american P. polymera Loew. 1. c. 40 has 16 joints in the male, and 

 14 in the female. These species have the joints of the flagellum, in 

 the male, deeply excised on the underside. P. macrocera has the 

 joints of the same shape, but only 13 of them. Thus therß is a gradual 

 passage from the normal number 13 to the abnormal 19. Megisto- 

 cera hraziliensis "Wied. the type of which I remember seeing in 

 Frankfort, Struck me at that time as a Pachyrrhina Avith long, fili- 

 form antennae, clothed with a dense, erect down (compare the figure 

 of the antenna in Wiedemann, A, Z. I, Tab. VI, f. 14). The number 

 of joints is the normal one, thirteen , and when Wiedemann , in the 

 letter-press says .twelve joints, he overlooks the minute terminal 

 Joint, distinctly marked in the figure. It would be ihexpedient to 

 introduce new genera for all these modifications in one organ only. 



PterelacMsus Rondani, Magaz. de Zool. 1842, Ins. pl. 106 was 



