ON THE NEW ZEALAND DIPTEROUS FAUNA. 199 
the woods, either resting or slowly flying. There are other 
members of this group recorded, always in small numbers, from 
different parts of North and South America, a few from Asia 
and Australia. The only country where they seem to be more 
abundant is Chili; some 19 species are described. Now from 
Greymouth alone I have eight species of Beridoe, and I see that 
several other species have been described from other parts of 
New Zealand. 
The genus Hrelophilus (family Syrphide) attracts my atten- 
tion next. Six species have been described from New Zealand 
(true Helophili, or closely allied forms), and in my very small 
collection I have, I believe, two new ones. Every collection from 
New Zealand is sure to contain a Helophilus, and most likely 
FTel, trilineatus, one of the earliest of Diptera described from that 
country (by Fabricius, in 1775, from the collection of Sir Joseph 
Banks). Only half a dozen Syrphid@ are recorded from New 
Zealand besides (elophilus, so that this genus seems nearly to 
absorb the whole family. Now the representation of the Syr- 
phide in a collection from any country in the world would be en- 
tirely different ; a small collection from any other country would 
probably contain several species of the genera Lvzstalis and 
Syrphus, before showing a single Helophilus. From New Zea- 
land not a single Arvzstalzs has been recorded yet, and only three 
Syrphi. 
Of the genus 7hereva my collection contains four species. I 
have seen two or three species in other collections. Thereva 
bilineata was likewise among the Diptera brought home by Sir 
Joseph Banks, and described by Fabricius. In this respect New 
Zealand seems again to be different from all the other faunas 
known tome. Tereve occur in all parts of the world, but by 
no means frequently ; they are not among the first Diptera that 
fall in the way of the collector. | 
The three instances which I have quoted (Berzs, Helophilus, 
Thereva) embrace about 25 species (described, or at least repre- 
sented, in collections), a comparatively large percentage, consi- 
dering that the whole number of species at present accessible to’ 
me (as specimens or as descriptions) is less than 200, And 
this proves thus far that the composition of the New Zealand 
dipterous fauna, I mean the relative proportion in which the 
different groups are represented, is a most peculiar one, more 
peculiar than any other fauna I know of. 
Another mode of enquiry open to us, even with very small 
materials, is to find out whether the collections within our reach 
contain any peculiar, exceptional forms, with a limited or dis- 
connected geographical distribution (especially as contra-dis- 
tinguished from cosmopolitan forms like Zabanus, Tipula, &c.) 
Of such forms I find several among my New Zealand Diptera. 
Limnobig, with pectinate antenne, seem to abound in New 
Zealand, and inthis respectthe fauna resembles that of Australia— 
I have not had the opportunity yet to determine further how 
Close this relationship is. A most interesting New Zealand 
