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The life-history and seasonal cycle of the Lepidopterous borer, Busseola fusca (Fuller), the most serious pest of maize in Southern Rhodesia, have been studied there.There are two generations in the year, the majority of the full-grown larvae of the second entering diapause, in which condition the dry season is passed in the maize stem, but a proportion of the second-generation consists of short-cycle individuals that give rise to moths irregularly during the dry season.In the field, the egg stage lasts about 7–11 days, according to the time of year. In the laboratory, there are six, very occasionally seven, larval instars in the first generation, occupying about 37 days, and the pupal stage lasts about 17 days. In the second (diapausing) generation there may be one or two additional moults without appreciable change in size, and there is considerable variation in the length of instars and in the date of entry into diapause, but by mid-June the bulk of the larvae that will survive are in diapause. The majority of diapause larvae pupate in early November, the pupal stage lasting about 23 days.The feeding habits of the larvae are described and reference is made to other food-plants.The length of life of the adult, in cage conditions, averages 6–7 days, but there is great variation. When provided with diluted honey, adults were not observed to feed, and absence of such food did not appear to impair egg-laying. The sex ratio was 1:1, but in catches at a light-trap the ratio of males to females was 5:1. Copulation takes place shortly after emergence, and oviposition may begin within 24 hours of emergence.The average number of eggs laid per female in cages was 360 over an average of four days, one female laying 1,032. Several batches of eggs may be laid in one night. A single mating appears to be sufficient, but males may copulate with more than one female. Eggs laid by virgin females do not hatch.Diapause is thought to be induced by larval feeding on drying food. Continuous rearing of non-diapause generations can be achieved by feeding the larvae on fresh, green maize. Similarly, in the field, irrigated out-of-season maize will support non-diapause generations and constitute a source of infestation that may render ineffectual the normal routine destruction of all plants of the previous dry-land farming season.The main parasite is the Tachinid, Sturmiopsis parasitica (Curr.), which may destroy more than 33 per cent, of the larvae in either generation.

On the basis of data collected by many observers dispersed through eastern Australia it is shown that Danausplexippus (L.) is present throughout the ycar in three defined coastal areas whereas in other areas its presence is seasonal. Breeding takes place throughout the extensive summer range but only in a restricted northeastern coastal area does it continue through winter, whilc the other two overwintering areas, the Hunter Valley-Sydney Basin and the Adelaide area, harbour non-breeding populations. Repopulation of the full summer range is achieved by spring spread from the reslricled winter iireas.

Trichadenotecnum enderleini (Roesler, 1943) is the only native species of the genus known from Australia to date. However, its exact systematic position is not firmly fixed mainly due to the lack of information on taxonomically and phylogenetically important morphological characters. In this study, T. enderleini is examined morphologically to clarify further its systematic position. The forewing markings and male terminal structures clearly show that the species lacks all apomorphies of Trichadenotecnum Enderlein, 1909 and is thus only distantly related to the genus. Therefore, T. enderleini is excluded from Trichadenotecnum. Ptycta floresensis Endang, Thornton & New, 2002 from Indonesia is considered to be the closest relative of T. enderleini, and T. enderleini is consequently transferred to the genus Ptycta Enderlein, 1925. As a result, Australia is excluded from the distributional range of Trichadenotecnum, except for T. circularoides Badonnel, 1955 considered to be introduced