The genus Cenocorixa Hungerford is shown to contain only eight valid species. New synonymy and systematic changes are given as is a revised key to males of the genus. Variation is noted in some of the characters used for specific identifications.

A series of constant observations on Amblyseius largoensis (Muma) on excised avocado leaves in the laboratory revealed that the hunger level of this predator directly affected the time spent feeding on individual prey, the relative aggressiveness, the frequency of successful captures, the length of digestive pause, and the speed of movement. Feeding and nonfeeding periods occurred in constantly recurring cycles. Hungry predators captured 2–4 prey in succession; after each capture a digestive pause followed, the length of which increased (up to 7–8 h) as the predator became increasingly satiated. This cycle was repeated 2–3 times in 24 h. Several thresholds appeared to be responsible for this behavior pattern.

The genus Phorocera Robineau-Desvoidy, 1830, is shown to be holarctic, divisible into a palaearctic element, the subgenus Phorocera, with three species, and its nearctic sister-group, the subgenus Pseudotachinomyia Smith. 1917, with eight, of which four, angustiforceps, auriceps, convexa and exigua, are described as new. P. webberi Smith, the type species of Pseudotachinomyia, is removed from the synonymy of slossonae (Townsend) and longiforceps Brooks is synonymized with slossonae. Keys, descriptions and figures are provided for the adults and eggs of the eight nearctic species, and oviposition in P. webberi is described. Relationships of Pseudotachinomyia with the s.g. Phorocera and with other exoristine genera are discussed.

Endecascelio stipitipennis n. gen. and n. sp. is described from Central Africa (former Belgian Congo). The extent and interrelationships of the tribe Embidobiini are discussed. A diagnosis of the tribe and a key to genera of the world is given.The genus Embidobia Ashmead is for the first time reported from the Oligocene of Baltic amber.

Addition of DL-α-tocopherol (vitamin E) at a level of 17.2 μg/g to an artificial diet containing casein, glucose, cellulose powder, salts, cholesterol, and a mixture of B-vitamins results in a loss of pigmentation in 30–50% of males on adult emergence. These albino males are of a light amber colour, apparently lacking melanin, although their cuticle appears to be sclerotized, and their sexual behaviour is normal.

Methyl laurate applied to the surface of house cricket eggs induces a melanization of the extra-embryonic fluid which is due to the oxidation and polymerization of dopamine. Melanization can be delayed or prevented by the addition of 5% vitamin E to the methyl laurate. Methyl laurate appears to activate a phenolase system in the extra-embryonic fluid, and this system or activation of this system is inhibited by vitamin E.

When fatty acid methyl esters or vitamin E are painted on the surface of eggs of the house cricket, Acheta domesticus (L.), second-stage larvae originating from these eggs may show reduction of the tarsi. The effect of the chemicals is on the first-stage larvae which absorb the chemicals through the tarsi during escape from the shell. The reduced tarsi are regenerated at the next moult or next two moults.

These studies show that Orgilus obscurator-purasitized Rhyacionia buoliana larvae initially gain weight in a manner similar to unparasitized larvae, but eventually attain a much smaller maximum size and then slowly decrease in weight with time. This decrease in weight is caused by the feeding of O. obscurator. The rate of increase in weight by O. obscurator increases with time during the second to fourth instars and decreases slightly during the fifth instar. During the fourth and fifth stages, the weight of O. obscurator changes from an initially minute proportion of the combined host–parasite weight to a significantly large proportion, eventually attaining ca. 80% of the combined weight. The feeding and activity of parasitized hosts remain high and continue for ca. 1 week longer than that of unparasitized hosts, resulting in a higher potential for damage to the host tree. Moulting of host larvae seems not to be affected by the presence of O. obscurator, although parasitized larvae remain in a "juvenile" state and do not develop testes. The implications of the size relationships of O. obscurator with its host on the activity of another parasite, Hyssopus thymus are discussed, and it is noted that parasitized hosts, on the average, needed fewer moults to complete their post-winter development than unparasitized hosts. This phenomenon is related to synchrony of the adult parasite with its host, and to host behaviour.

In Canada and Alaska, the Stratiomyidae are represented by six subfamilies containing 23 genera (less Caloparyphus) and 84 species. This paper treats three of the subfamilies, the Beridinae, Sarginae and Clitellariinae which include 15 genera and 21 species.The vast amount of information that has accumulated over the years since 1927 when Dr. Corran published his synopsis of the family has been assembled and reviewed. This includes recent changes in nomenclature, information on adults and immature stages, notes on biology and distribution records. In addition, keys have been provided for adults and larvae (where possible) at the subfamilial, tribal, generic and specific levels.

The preferred host of the cluster fly, Pollenia rudis Fab., in Ontario is reported to be the earthworm Eisenia rosea Sav. Periodic field digging revealed the immature stages of P. rudis feeding, or in close association with, E. rosea. In addition P. rudis was reared in the laboratory on E. rosea but could not be reared on any of the other species of earthworm found in the field.For the first time in North America the complete life history, along with each of the immature stages of P. rudis, is described. The differences between P. rudis from North America and those from France are indicated.Finally, the authors speculate that there are two strains, or species, of P. rudis in France: one is host-specific to the earthworm Allolobophora chlorotica Sav. and the other to E. rosea. Only the strain with E. rosea as its preferred host has as yet been reported from Canada.

A detailed analysis of male courtship behavior in Phodaga alticeps LeC. is presented. Although behavior in this species shares the basic pattern characterizing the subfamily Meloinae, several unique features are present. These include the mounted male being supported primarily by the substrate rather than the body of the female, and the anterior positioning of the male’s middle legs during most of the courtship period. Male stimulation of the female is tactual in nature and consists of periodically curling the antennae around those of the female and at the same time stimulating her maxillary palpi with the middle legs. Bouts of tactual display alternate throughout courtship with periods of male quiescence. Genital insertion attempts are rare in this species and probably occur only prior to copulation. Besides a description of male behavior the structural modifications functionally correlated with courtship are described; and concomitant female behavior and its effects on the male are discussed. In addition, the pattern of courtship in P. alticeps is compared to that of other meloids. Particular attention is given to behavior in its closest relative, Negalius marmoratus Casey.Other aspects of the bionomics of P. alticeps are also treated in this paper. Geographic distribution, seasonal distribution, feeding behavior, defense, antennal cleaning, and oviposition behavior are stressed.

A method is described for rearing and selecting strong, robust populations of first-stage root larvae for bioassay of insecticide toxicants in soil and host plant tissue. Oviposition dishes are placed in cages with flies for a 6-hour period 3 times a week. The eggs are then incubated on silk cloth over moist blotting paper in petri dishes at 21° to 22 °C until they hatch. When the larvae move away from the empty egg cases to a food supply, they are transferred to the centre of another piece of silk cloth lying fiat on a wet sponge. The strongest of the larvae move most quickly outward from the central mass and are transferred to holding trays and later set up for bioassay with plant tissue or treated soil. The weaker larvae are discarded. In 24- to 48-hour tests with larvae obtained by this method, there was no mortality in untreated samples. When larvae were reared to maturity, mortality in untreated media averaged approximately 6% in several hundred tests conducted from 1969 to 1971.

A list is given of 32 species of aphids, with their host plants, from Thailand. Males and oviparae of Aphis craccivora Koch, a male of Rhopalosiphum maidis (Fitch), and an ovipara of Tinocallis kahawaluokalani (Kirkaldy) were collected. Tritrichosiphum thailandicum new genus, new species is described.