378 M. IF. Meinert on Mochlonyx (Tipula) 
recognizable larval form; for in the few years that I have 
specially studied our midge-larvee I have found this larva dis- 
tributed from Ruderhegn in the north, to Boserup Skov 
in the west, and Valle in the south; even in Dyrehave, 
not far from Ordrupsmose, Steger’s favourite collecting-place, 
I have met with it in great abundance; and it also occurs in 
the collection of larva: in the University Zoological Museum. 
However, it is a fact well known to collectors that many 
animals have certain periods during which they nearly dis- 
appear, and others in which they occur abundantly. 
When we say that Zetterstedt did not know T%¢pula culici- 
formis as Danish or Scandinavian, it must be borne in mind, 
nevertheless, that in his first treatment of the genus Corethra 
(2. c. p. 8475, note 2) he remarks that Wahlberg, perhaps, 
was acquainted with it :—‘ In annotationibus mecum commu- 
nicatis dixit Cel. Prof. Wahlberg, se ad Gusum Ostrogothiz 
et ad Holmiam Corethram culiciformem invenisse. Si vero 
eadem ut nostra C. fusca aut Degeerii C. culiciformis sit 
habenda, dijudicare non possum, cum specimina Wahlber- 
giana cum nostris comparare non potui.” It may also be 
noticed that in the ‘ Diptera Scandinavie,’ tom. xi. seu 
supplementum tertium (1855), p. 4837, he cites Corethra 
velutina, Ruthe, as new for the Scandinavian fauna; for it is 
possible that Z%pula culictformis is here intended, and, in any 
case, it seems to me nearly certain that this species may belong 
to the same genus as C. culiciformis, as will appear from what 
follows. 
Schiner also (‘Fauna Austriaca: Die Fliegen (Diptera),’ 
Bd. 1. 1864) did not know Tipula culiciformis, but simply 
cites it among the European species occurring outside of 
aa ae referring to De Geer’s description in his ‘ Mémoires,’ 
iC. 
But while the species thus seems to have disappeared, or 
not to have been met with since De Geer’s time, and the 
genus Corethra, as that genus is now formulated with C. plu- 
micornis as the type species, does not agree with 7. culici- 
formis, another genus, Mochlonyx, has been established, to 
which it would appear that De Geer’s species may fairly be 
referred*. The establishment of this genus took place as 
follows :— 
* Strictly speaking, the generic name Corethra should be retained for 
Tipula culicifornis, De Geer ; and when other species, such as Corethra 
plumicornis and paliida, were afterwards proved to belong to a different 
genus from this first-named species, a new generic name ought to have 
been selected for them. But I regard it as very hazardous to introduce 
changes of name for such a well-known species as C, plumicornis, which 
