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B.—Producers of Pathological Conditions

The species of the Family Calliphoridae listed in Table 6 are all known sheep maggot flies. Calliphora laemica and Lucilia sericata are the primary sheep maggot flies in New Zealand (Miller, 1939), while Lucilia cuprina is the most important primary species in Australia (Mackerras, 1936). These insects cause blowfly strike, their maggots invading the living tissues of sheep, so causing myiasis. One female of C. laemica, a species native to New Zealand but not found in Australia, entered a DC4 following its arrival from the latter country in December, 1946, and deposited a number of living larvae when captured. Two living adults and many larvae of the widespread L. sericata were collected from a garbage can in the kitchen of a DC6 which arrived at Whenuapai from North America on 12th November, 1950. This species is established in Hawaii (Bryan, 1934) and Canton Island (Van Zwaluwenburg, 1943), and the examples which reached Whenuapai could have come from either of these places. Aircraft from Fiji twice harboured living examples of L. cuprina, an almost cosmopolitan species which has been introduced into that country (Bezzi, 1928). None of the other three species of Calliphoridae listed are of primary importance as sheep maggot flies. Single examples each of Calliphora erythrocephala and C. rufipes were taken alive in the astrodome and passenger compartment of a DC4 from North America, although there is a possibility that these may have flown on board following the completion of insecticidal spraying at Whenuapai. A single dead example of Chrysomyia rufifacies found in the passenger compartment of a DC6 from North America might have come on board at the airport in either Hawaii (Bryan, 1934) or Fiji (Bezzi. 1928).

The sheep maggot fly problem is of great importance to both Australia and New Zealand, the prosperity of which is so closely bound up with sheep-raising. The possible interchange between the Pacific islands and these countries of not only new species of sheep maggot flies but also dangerous strains of species already represented by harmless strains is obviously rendered possible by air transportation.