Head capsule measurements of the ambrosia beetle Xyloterinus politus (Say) revealed three larval instars. The xylomycetophagous larvae lengthened their cradles and a positive correlation existed between head width and cradle length. A sex factor of 0.84 was in favor of the female adults. Dissection of active galleries revealed only a single female per gallery. Males were never seen to initiate or excavate a gallery and were forced from the entrance hole by the female when placed in an active attack. The gallery system studied was simple, the entrance hole penetrated into the sapwood for a variable distance before it branched into secondary tunnels at right angles to the main gallery.

Eggs were laid singly in cup-shaped cradles excavated by the female. The cradle openings were plugged with frass throughout the duration of the immature stages. Callow adults emerged from the cradles by forcing the frass plug covering the entrance, and re-entered, their position reversed to feed upon the ambrosial fungus growing on the cradle walk X. politus overwintered as an adult in the old cradles and galleries. Larvae of Ipideurytoma sp. (Hymenoptera: Eurytomidae), probably a larval parasite of X. politus, were found in cradles.

Microscopic examinations revealed that free-floating hard black bodies in larvae, pupae and adults of the Swaine jack-pine sawfly, Neodiprion swainei Midd., often contained polyhedra. A simple and rapid method for detecting the presence of the virus infection before gross symptoms appear is described.

This paper reports on studies of biology and life history of the Zimmerman pine moth, Dioryctria zimmermani (Grote), in southern Michigan.

Adults emerged during the last 3 weeks of August and eggs hatched through mid-September. Eggs were laid almost entirely on the main stem and, upon hatching, the larvae entered recesses in the bark and spun hibernacula, ostensibly without feeding.

Studies on the vertical distribution of larvae and pupae showed a fairly uniform distribution over the main stem in spring and early summer. In late summer, a larger percentage was found in middle whorls.

Based on head capsule measurements, it is tentatively proposed that there are six larval stadia. Occurrence of parasitism in the last larval stadia is discussed, and a new egg parasite is reported.

The presence of D. abietivorella Grote in the study areas is noted, and discussed briefly.

Results of the analyses for digestive enzymes in the glands and midguts of five species of ants showed that invertase is usually secreted by the maxillary glands, amylase by the salivary glands, and protease and lipase by the midgut. Lipase was found in the post-pharyngeal glands but observations indicate that it is not associated with the digestion of ingested food. Differences in the activity of the enzymes in different species tended to reflect the feeding habits of the ants.

An examination of North American and Siberian adults of Holarctias indicates that H. sentinaria (Geyer) occurs only in the Nearctic. It differs from the Siberian species, H. rufinaria (Staudinger), in colour pattern of the wings and in the shape of the cornutus of the male genitalia. Specimens named H. magnetaria (Guenée) in North American collections should be re-examined and most, if not all, placed in the genus Scopula Schrank.

A study was initiated to determine the effects of various constant and alternating temperatures on the survival and development of the immature stages of Culiseta inornata (Williston). Eggs did not hatch at 2° and 5 °C. but at 10°, 15°, 21° and 26 °C. between 83 and 96% hatched. Larvae required up to 239 days to reach the pupal stage at 5 °C. but no adults emerged at this temperature. The optimum temperature for rearing C. inornata was near 21 °C. Temperatures below 21 °C. caused an extended period of development; above 21 °C. high mortality occurred among late instar larvae and pupae.

The subfamily Acicnemidinae is for the first time recorded in America, descriptive details and illustrations are given for its introduced representative, the European Trachodes hispidus (Linnaeus), notes on the distribution and synonymy of Acicnemidinae and Trachodes are presented, and the subfamily keys of Blatchley and Leng and of Kissinger are emended to include the Acicnemidinae.

Woodpeckers consume wood-boring larvae of families Siricidae and Melandryidae leaving three distinct types of mark on the tree. The distribution of marks in relation to decreasing prey population indicates that tapping is the principal means of locating larvae. Forty per cent of siricids and two per cent of melandryids are consumed by woodpeckers on individual feeding trees; as siricid population increases the proportion of larvae taken decreases.

Eggs of Rhagoletis pomonella (Walsh) laid in Siberian crab, Malus baccata Borkh., hatched, but the larvae did not develop beyond the first instar. The small amount of feeding indicated that death occurred within a few days after hatching. Similar incidents of complete mortality occurred in the crab apples of Malus toringoides Hughes, Dupont Flowering, Henrietta Crosby, and Almey that were infested in the laboratory. Larvae were able to complete their development in the crab apples of Bedford, Pink, Beauty, Dolgo, Virginia, and Chestnut. The causes of this mortality are unknown.

The nominal genera Mimocomma Warren, Polychorista Warren, and Parudea Swinhoe are synonymized with Thliptoceras, and Prophantis Warren is removed from synonymy. Twenty previously described nominal species are referred to Thliptoceras; of these, 12 are recognized as valid. The following nominal species are referred to Thliptoceras for the first time: Circobotys marginalis Hampson, from Crocidophora; Mimocomma fulvimargo Warren, from Crocidophora; Salbia althealis Walker, with its three synonyms, Botys cydipeialis Walker, Botys tisiasalis Walker, and Phycidicera manicalis Snellen, all from Deba; Botys gladialis Leech, from Crocidophora; Crocidophora rufitinctalis Hampson; Ebulea decoloralis Warren, from Loxostege; Pyrausta torridalis Hampson; Phlyctaenodes decoloralis sinensis Caradja, from Loxostege; Parudea fimbriata Swinhoe; Crocidophora artatalis Caradja; Botys fuscocilialis Snellen, from Pyrausta. Lectotypes are designated for: Hapalia cascalis Swinhoe; Thliptoceras variabile [-is] Swinhoe; Thliptoceras epicrocale [-is] Swinhoe; Circobotys marginalis Hampson; Botys gladialis Leech; Ebulea decoloralis Warren; and Crocidophora artatalis Caradja. Thliptoceras rufitinctale (Hampson) is sunk as a junior synonym of T. gladiale (Leech) and T. torridale (Hampson) as a junior synonym of T. decolorale (Warren). T. sinense (Caradja) is considered a distinct species and not a subspecies of T. decolorale (Warren). T. buettikeri is described as a new species from Thailand.

Development time decreased with each increase in rearing temperature in Aedes vexans, A. nigromaculis, and Culiseta inornata until the optimum survival temperature was reached. The optimum survival temperature for A. vexans was 26.5 °C, for A. nigromaculis 21 °C, and for C. inornata 21 °C. Dry weight gain per hour in female larvae was greater than in male larvae in all three species, at all temperatures. There was a significant reduction in weight in each larval instar, pupal, and adult stage, with each 5.5 °C increase in rearing temperature. Times to larval–pupal ecdysis and pupal–adult ecdysis were the same for males and females of A. nigromaculis at all developmental temperatures tested. Time to larval–pupal ecdysis and pupal–adult ecdysis in A. vexans and C. inornata occurred 1 to several days later in females, depending upon the developmental temperature. In all three species the duration of the fourth instar was longest and the specific weight gain greatest.

Corthylus columbianus Hopkins became permanently established in. the study area in southern Indiana during 1940–62. Three epicenters were present in 1945. Two of these shifted, expanded, and merged the following year. The two remaining epicenters merged during the first outbreak. As the population declined after the first outbreak and began retreating toward the center of the stand, two epicenters were again definable. One of these alternately expanded and contracted for several years demonstrating, qualitatively, that epicenters are definable and dynamic in time and space. That is, any particular locus undergoes some degree of areal shift each year and varies in size through time.

Quantitatively, attack and egg cradle densities within the epicenters follow the same pattern. Densities were generally lowest in the newly invaded areas. Except during epiphytotics, highest density areas were usually aggregated near the center of the stand, but shifted from year to year. For example, only one tree contained a high density in 1954; by 1956 the high density area had shifted spatially and encompassed 10% of the study trees.

An “indigenous population” of C. columbianus is an areal concept. The insect withdrew to certain areas, not certain trees, during times of low population numbers. The “brood” tree concept–a single tree containing all or a majority of the population during times of low population numbers–is rejected in the case of the Columbian timber beetle for the study area in southern Indiana.

Tamalia pallida and Tamalia keltoni are described as new from Mexico and compared with T. coweni, the only other known member of the genus. A key to species is given.

The species described as Pachynematus gregarius Marlatt is removed from the genus Micronematus and placed in the genus Eitelius. A key to the males and females of the two known species of Eitelius, and illustrations, are provided.

Females of Scambus buolianae did not lay eggs when deprived of food in the form of host tissues throughout adult life. Greatest egg-production and longest life resulted when that food was continuously available. Average egg-production was reduced to under one-third, and longevity reduced to two-thirds or one-half, in females that were permitted to feed on host body fluids only intermittently or that were deprived of them after the first 15 days of adult life. No eggs were laid by females deprived for the first 20 days, and longevity was reduced to one-third. However, absence of host body fluid as food during the first 15 days only did not significantly reduce egg-production or length of life. Tests showed females of S. buolianae have distinct and similar relative preferences for different host species as sources of body tissues for food. Both sexes showed distinct and similar preferences for species of wild flowers as sources of carbohydrate. The results support earlier findings and show that the presence or absence of suitable foods for the adults may determine whether or not an introduced parasite can establish itself, and can influence the effectiveness of existing parasites as biological control agents.

Penenirmus zeylanicus from Megalaima zeylanica and P. rafflesi from Megalaima rafflesii are both described as new. Penenirmus from African barbets are listed and the new species compared with those known from the Picidae.

One male of this species was collected in a light-trap on 28 June, 1967 at Chatterton, Hastings County, Ontario. This appears to be the first record of A. thibaulti Dyar and Knab in Canada.

A study was made of the poplar-and-willow borer, Sternochetus (= Cryptorhynchus) lapathi (L.) (Coleoptera: Curculionidae), in British Columbia between 1959 and 1964. The borer occurred principally south of 52 degrees north latitude. Willows were the preferred hosts. Ornamentals, hybrids in commercial plantings, and natural growing trees were attacked. The life cycle of the insect on southern Vancouver Island lasted up to 3 years; overwintering took place in early instar and adult stages. Eggs were laid in the bark; larvae mined first in the bark and then in the wood, where pupation took place. Few parasites and predators were found. DDT, dieldrin, and BHC killed adults; lindane (0.5% water emulsion), applied in the spring, caused larval mortality up to 96%.

Insect eggs and small organisms may be removed from foliage or bark with solvents and recovered on filter paper. Tests with Acleris variana (Fern.) showed that 96 per cent of eggs were recovered compared to 47–70 per cent counted on foliage. Tests indicated that the extraction method required one-third to one-tenth the time spent in counting the organisms on foliage. The extraction method was more consistent than counts on foliage, and less affected by differences in personnel and working conditions. The method and the solvent must be selected and modified to suit the organism.

Tinocallis Matsumura is a small group of aphids that is mainly associated with the Ulmaceae. Eight species are known, as follows: Tinocallis ulmiparvifoliae Matsumura, T. platani (Kaltenbach), T. saltans (Nevsky), T. zelkovae Dzhibladze, T. zelkowae (Takahashi), T. ulmifolii (Monell), T. caryaefoliae (Davis), and T. kahawaluokalani (Kirkaldy). All are redescribed and an illustrated key is offered.