250 
The N.Z. Journal of Science and Technology. [July 
The most satisfactory method of control is the destruction of larvae 
and their breeding-places. The main features to be noticed are the removal 
where possible of all collections of water— e.g., in old tins, roof-gutters, 
bottles, rain-puddles, &c.- the screening of water-barrels, or adding 1 part 
of copper sulphate to 5,000 parts of water, which will destroy the larvae, 
but will not affect the water for drinking purposes. In the case of larvae 
living in streams and pools the introduction of small fish has been of value ; 
ducks are also beneficial. 
A common practice is oiling the surface of water with kerosene, 
petroleum, &c. ; the lighter oils may be sprayed on the water. The follow¬ 
ing larvicide was found to be very successful in the Panama Canal zone : 
150 gallons of carbolic acid is heated in a tank to the temperature of 
212° F., then 150 lb. of powdered or finely broken resin is poured in, 30 lb. 
of caustic soda is then added, and solution kept at 212° F. until a perfectly 
dark emulsion without sediment is obtained. The mixture is thoroughly 
stirred from the time the resin is put in until the end.” One part of the 
emulsion in 5,000 parts of water is recommended. It is diluted one-sixth 
and sprayed on the water, even on moderately flowing streams. There 
are several other larvicides mentioned. In large swamp areas oiling is 
sometimes resorted to, but the most satisfactory results are obtained by 
extensive draining. I). M. 
Studies in Australian Mecoptera. No. 1, The New Family Nannochoristidae, 
with Descriptions of a New Genus and Four New Species ; and an 
Appendix descriptive of a New Genus and Species from New Zealand, 
by R. J. Tillvard. Proc. Linn. Soc. N.S.W., vol. 42, pt. 2, pp. 284-301, 
1917. 
The small order Mecoptera, or scorpion-flies, is still treated by the more 
conservative entomologists as a family of the Neuroptera, but Dr. Tillyard 
considers that its separation into a distinct order rests on absolutely un¬ 
assailable foundations, and promises to deal later with the view of Handlirsch 
that it is ancestral to the Trichoptera, Lepidoptera, and Diptera. Though 
small in its number of species at the present day, the fossil record leads 
to the belief that it was more abundant in past days. Dr. Tillyard has 
already described a fossil representative from the Triassic beds of Ipswich, 
Queensland, and now announces the discovery of other fossils from the 
Wianamatta shales and the Permo-Carboniferous beds of' Belmont, near 
Newcastle, N.S.W. In the present paper a number of Tasmanian specimens 
are placed in the new genus Nannochorista, which is stated to be an example 
of a highly specialized reduced type based upon a very archaic foundation. 
“ It seems clear that the discovery of this remarkable new type of insect 
is of the greatest interest to students of all the Panorpid orders, and 
cannot fail to influence very greatly our views upon the phylogeny of the 
Lepidoptera and Diptera, as well as radically altering our conception of the 
Mecoptera as an order preserving an original freedom of action between 
fore- and hind-wings.” 
In an appendix Dr. Tillyard describes a pair of specimens from Queens¬ 
town and Longwoods, N.Z., forwarded to him by Mr. A. Philpott, of 
Invercargill, for which he makes the new genus and species Choristella 
philpotti. He remarks : “I have little doubt that this insect would be 
found in any of the mountainous regions of the South Island, especially 
along the borders of lakes and small mountain-streams. . . . The 
bearing of this discovery upon the Antarctic theory as advocated by 
