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A new invertebrate-associated fungus, Ophiocordyceps furcatosubulata, is reported from China, Vietnam and Laos. It is characterized by solitary stromata, clavate and slender stipes, cylindrical fertile parts, furcate and subulate sterile apices, immersed perithecia, short asci, filiform ascospores with multi-septa, short secondary ascospores, hirsutella-like asexual morph with polyphialidic conidiogenous cells, broadly ellipsoid or ellipsoid conidia, and on larvae of elaterid beetles buried in soil. Both morphological observation and phylogenetic analyses of combined nrSSU, nrLSU, tef-1α, rpb1 and rpb2 sequence data support that this fungus is a distinctive species in the genus Ophiocordyceps.

SUMMARYPlant leaves that are exposed to herbivore induced plant volatiles (HIPVs) respond by increasing their defenses. Whether this phenomenon also occurs in the roots is unknown.Using maize (Zea mays), whose leaves respond strongly to leaf HIPVs, we measured the impact of root HIPVs, emanating from plants infested by the banded cucumber beetle (Diabrotica balteata), on constitutive and herbivore-induced levels of root soluble sugars, starch, total soluble proteins, free amino acids, volatile and non-volatile secondary metabolites, defense gene expression, growth and root herbivore resistance of neighboring plants.HIPV exposure did not alter constitutive or induced levels of any of the measured root traits. Furthermore, HIPV exposure did not reduce the performance and survival of banded cucumber beetle larvae on maize or teosinte. Cross-exposure experiments revealed that maize roots, in contrast to maize leaves, neither emit nor respond strongly to defense-regulating HIPVs.Together, these results demonstrate that volatile-mediated defense regulation is restricted to the leaves of maize and teosinte, a finding which is in line with the lower diffusibility of volatiles in the soil and the availability of other, potentially more efficient information conduits below ground.

The susceptibility of rhinoceros beetle larvae, Oryctes agamemnon, to different concentrations of Syzygium aromaticum cloves was studied under laboratory conditions. Two forms of cloves were applied, first as finely powdered flower buds and later as an essential oil. The clove powder concentrations used against the larvae were 1, 3, 5, 7 and 9 %, and the clove essential oil (CEO) was used at concentrations of 1, 2, 3, 4 and 5 %. The highest (68.5 %) and lowest (2 %) larval mortality were caused by 9 % and 1 % clove flower bud powder (CFBP), respectively. However, the CEO was more effective against the larvae of O. agamemnon than the powder. Mortalities ranged from 12.5 to 87.9 % at oil concentrations of 1 and 5 %, respectively. The results also showed that the two forms of cloves persist in the treated soil for 7 to 8 days. Additionally, the clove oil and powder have a residual effect in treated soil that provides sustainable protection for date palms against root borers. Accordingly, it was concluded tha...

On the basis of fungi isolation from the Colorado beetle larvae three species of Botrytis have been isolated: Botrytis sp., B. bassiana Bals., B. fusca Sacc. and others.

Weak and small honey bee colonies are supposed to be more susceptible to infestations by the small hive beetle [Aethina tumida, small hive beetle (SHB)]. To test this, we established 24 nucleus colonies [12 with and 12 without previous SHB removal (= screening)]. Four weeks later, we compared beetle numbers and the occurrence of SHB reproduction to the corresponding full-sized colonies. Full-sized colonies with no screening were infested with significantly more SHBs than all other groups (mean ± standard deviation = 46.9 ± 26.7). Regardless of this, none of the full-sized colonies showed damage or evidence of SHB reproduction. In contrast, five nucleus colonies collapsed and SHB larvae were found in an additional seven colonies. Our study demonstrates that SHB infestation levels which are harmless to full-sized colonies may have a negative impact on small nucleus colonies.

The developmental times of mealworm beetle larvae, Tenebrio molitor were studied at six temperatures ranging from 15 to with 60~70% RH, and a photoperiod of 14L:10D. Mortality of larval period was very low at 17 and but did not die over . Developmental time of larva was decreased with increasing temperature. The total developmental time of T. molitor larvae was longest at (244.3 days) and shortest at (110.8 days). Egg and larvae were not developed at . The lower developmental threshold and effective accumulative temperatures for the total larval stages were and 2564.1 degree-days, respectively. The relationship between developmental rate and temperature was fitted by a linear model and nonlinear model of Logan-6(

New approaches for wood protection based on green technologies have increased interest in using heartwood portions of certain wood species for the effects (toxic and antioxidant properties, chelate formation, hydrophobicity) of extractives located in heartwood. This study evaluated the biological performance of heartwood of Liquidambar orientalis Mill., trees well-known for production of balsam. Heartwood specimens were subjected to soil-block decay tests based on the American Wood Protection Association standard method using two brown-rot and two white-rot fungi. Specimens were also subjected to two different laboratory termite resistance tests. Additionally, heartwood specimens were tested for mold growth and resistance to furniture beetle larvae. Laboratory fungal decay resistance tests showed that the heartwood of the tree was not resistant against the fungi tested; however, the wood was resistant against termites and furniture beetle larvae in laboratory conditions. Mold tests revealed that the wood also showed resistance to mold growth. Complete biological resistance was not achieved in this study, suggesting that heartwood extractives do not directly correspond to resistance to wood-degrading fungi.

Vertebrates show different tendencies in regard to their preference for seeds or fruits infested by insects compared to non-infested ones. Behaviour may include rejection of one type, preferential consumption of one type or no differentiation among them. When comparing infested versus non-infested fruits, most studies have focused on energy content and nutritional components of the food items; but the energy input provided to the consumer is a better measure for the comparison of the value of each type of food. In this study, I calculated the energy assimilated by rodents for the seeds of the palm Attalea butyracea contained in non-infested endocarps and from bruchid beetle larvae contained in infested endocarps. Using the energy assimilation and time of handling by rodents for both types of endocarps, I quantitatively demonstrated that both infested and non-infested endocarps produce a similar energy input. This finding is consistent with the previous hypothesis that there is a trade-off between the energy content and the time required to extract the insect larvae compared with the seeds in endocarps of Attalea butyracea.

The larva of Siagona europaea Dejean, 1826 collected in the field with a new type of trap, the bait trap, is described. As an adult, this is a myrmecophagous beetle; however, until 2003, in ten years of research no larvae had been found in the field when excavating deep holes around Messor nests in clay soils, in which to place the usually employed pit fall traps. Therefore, a new type of trap was adopted, i.e. a subterranean trap positioned where the main soil crevices intersect. One larva of second instar and one of third one were studied. Most larval features are atypical of carabid beetle larvae and, in particular, the form and structure of the head appendages and the form and insertion of the urogomphi are of interest. Moreover, the larva of S. europaea is completely blind, no trace of stemmata being present in either instar. Its morphology, as well as the recording of its behaviour in the lab, point to it being a ‘runner’, exploring the subterranean crack system of clay vertisols.

Mechanical barriers consisting of bands of polyethylene terepthalate resin attached to wooden posts by latex caulk adhesive and staples were 100% effective in preventing passage of dispersing lesser mealworm, Alphitobius diaperinus (Panzer), larvae in the laboratory. Barriers continued to be 100% effective after being held in a caged layer poultry house for 3 mo. Polyethylene terepthalate barriers installed on support posts in a pullet house in Brooker, FL, were >92% effective against natural populations of lesser mealworm larvae 6 mo after installation. The barriers also were >94% effective against natural populations of larvae of the hide beetle, Dermestes maculatus DeGeer, when fly populations were low. Fecal spot depositions by house flies in excess of 31 cumulative fly spots per square centimeter on spot cards reduced the effectiveness of the barriers to 79–90%, and barrier efficacy was reduced to 40–56% when fly spots covered >80% of the surface of the plastic. Washing the barriers with water to remove fly spots restored their effectiveness against hide beetle larvae to >99%.

I examined the impact of Tetraopes tetraophthalmus (Forster) on its host plant, Asclepias syriaca L., through a series of field observations and experiments. Adult beetles feed on milkweed flowers and foliage while larval beetles feed on the rhizomes of milkweed. Strong negative effects of beetle herbivory on milkweed growth, but not sexual reproduction, were found in experiments comparing growth for milkweed patches from which adult beetles were removed to controls with an unmanipulated abundance of beetles. Experiments using potted milkweed revealed a strong negative effect of beetle larvae on the growth of milkweed roots and rhizomes. Under natural field conditions, I could detect no effect of adult beetle density on the growth or sexual reproduction of milkweed. Overall, it appears that below ground herbivory by beetle larvae negatively impacts milkweed growth, but detection of these effects under natural conditions are confounded with a number of factors.

Freeze-avoiding fire-colored beetle larvae, Dendroides canadensis, were monitored seasonally to explore the role of endogenous hemolymph ice nucleators and antifreeze proteins on the maintenance of supercooling. In preparation for overwintering, D. canadensis depressed hemolymph ice nucleator activity and increased thermal hysteresis activity [mean value circa 0. 5 °C (summer) versus circa 5 °C (midwinter)] resulting in decreased larval and hemolymph supercooling points [−7 °C (summer) versus −20 °C (midwinter)]. Results of gel filtration chromatography, flotation ultracentifugation and quantitative investigation of ice nucleator activity using hemolymph from summer and winter collected larvae strongly suggest that highly active protein and lipoprotein ice nucleators are removed in preparation for overwintering. Additions of either purified antifreeze proteins or midwinter hemolymph with high antifreeze protein activity to a mixture of protein or lipoprotein ice nucleators isolated from D. canadensis hemolymph inhibited the activity of these nucleators. This suggests that in addition to seasonal removal, inhibition of hemolymph ice nucleators by antifreeze proteins contributes to seasonal increases in hemolymph supercooling capacity.

Insect Genomics![Figure][1] Asian longhorned beetle larvae digest wood by using acquired genes. PHOTO: SCOTT CAMAZINE / ALAMY STOCK PHOTO The larvae of the invasive Asian longhorned beetle burrow into and kill trees. On sequencing the genome, McKenna et al. found that gene transfers from

Cordyceps brunneapunctata is described from elaterid beetle larvae buried in forest soils in Thailand where it is found associated with a Hirsutella state. Isolations were made from ascus part-spores, conidia and from hyphal material within the host and all grew in an identical manner.

The bruchid Bruchidius atrolineatus (Pic) causes significant damage to the stored protein rich seeds of cowpea, Vigna unguiculata, in the West African Sahel. Twenty varieties of cowpea were evaluated for susceptibility to attack by B. atrolineatus in the laboratory. The bruchid showed differential response to the seeds in terms of developmental period, percentage adult emergence, seed weight loss due to feeding by one larva, adult weight at emergence and life-time fecundity of females reared from them. Based on these criteria, IT85F-2205 and IT84S-275-9 were the least susceptible varieties. The development of B. atrolineatus was most significantly delayed in these varieties. The beetle larvae consumed less of their seed material and adults reared from them were smallest and least fecund. The varieties IT87S-1393, IT90K-391 and IT84D-460 also had relatively lower susceptibility to the beetle than others. In a no-choice oviposition experiment, B. atrolineatus females laid equally on all varieties. Percentage egg hatch on the different cowpea varieties did not differ significantly. The results are discussed in relation to previous reports on susceptibility of cowpea and other legumes to bruchids.

Oryctophila bonaerensis sp. nov. parasitizing curculionid beetle larvae from Argentina, is described and illustrated. The species is characterized by a prominent genital cone and a short and filiform tail appendage. Female with vulva at midlenght of body, vagina long, S-shaped, monodelphic, opistodelphic. Male with one club-shaped spicule. Genital papillae arranged as follows: one pair of large preanal papillae and three pairs of postanal papillae of various sizes: a pair of medium sized papillae is immediately posterior to the anus, followed by a pair of large papillae, and one pair of small papillae at the base of the caudal appendage., Centro de Estudios Parasitológicos y de Vectores

Aqueous suspensions produced by grinding leaf tissue of tansy, sage, basil, catnip, dill, and rue in water deterred feeding of adult and larval Colorado potato beetles, Leptinotarsa decemlineata (Say), when tested on eggplant leaf disks in laboratory choice tests. Tansy showed the most potent antifeedant effect. Adult beetles refused to feed on leaf disks dipped in a 10% (2 g in 20 ml) suspension of tansy tissue, even after 22 h in either a choice or no-choice situation. Beetles kept for 22 h on leaf disks treated with a 1% (0.2 g in 20 ml) tansy suspension subsequently rejected the treatment to the same extent as naive beetles. Tansy treatments caused substantial mortality to beetle larvae that fed on them from egg hatching. These effects could have been caused by starvation or physiological toxicity. Tansy and other herbs show potential for use in integrated pest management programs aimed at the Colorado potato beetle.

Alternatives for control of soil-inhabiting pests are needed due to the phase-out of methyl bromide. One possible alternative is using the pesticidal properties of compounds released by macerated Brassica tissues. In this study, larvae of masked chafer beetles (Cyclocephala spp.) were placed in soil amended with Brassica juncea L. (PI 458934) tissue. Allyl isothiocyanate (AITC) levels were positively correlated to larval mortality, with the 8% B. juncea treatment resulting in 100% larval mortality with an average AITC concentration of 11.4 mg per liter of soil atmosphere. Although B. juncea produces high levels of AITC, the mass of tissue required for significant insecticidal activity against Cyclocephala spp. also is high, between 4 and 8% of soil mass for this plant accession. Accepted for publication 23 May 2002. Published 10 June 2002.

The beetle Dermestes maculatus, which is known to feed on dry, protein-rich, stored materials, has lately become a pest of wood and insulating polymers of poultry houses. Its carnivorous attack on live birds is recorded in this paper for the first time. These attacks resulted in deep wounds to adult male turkeys. When beetle larvae were offered simultaneously calf meat, chicken meat, and pellet feed for rodents, no clear preference was noted.

The development of alternative methods for control of soilborne pathogens is imperative since the U.S. Clean Air Act bans the use of methyl bromide after 2005. One possibility is to exploit the pesticidal properties of compounds released by macerated Brassica tissues. In this study, masked chaffer beetle larvae were placed in sealed 473-mL jars with 335 g of soil amended with 1%, 2%, 4%, or 8% (g·g–1) Brassica tissue. The most prevalent volatile toxic compound of Brassica juncea (PI 458934) is allyl isothiocyanate (AITC). AITC production was measured in the jars at 0.25, 4, 8, 24, and 48 h using a solid-phase microextraction device (SPME) and gas chromatography. After 7 days, larvae mortality was determined. Control treatments included untreated soil, soil amended with 8% tomato plant tissue, soil amended with pure AITC, and untreated soil with an atmosphere of ≈20% O2 and 0% CO2 changing over 48 h to 2% O2 and 20% CO2. AITC levels were positively correlated to larvae mortality. The estimated lethal concentration for 50% kill (LC50) was 3.6 μg AITC/L soil atmosphere. AITC levels may be influenced by Brassica mass added, soil bulk density, and environmental factors including temperature and moisture. B. juncea has a high tissue AITC concentration. However, the mass of Brassica tissue required for insecticidal application against Cyclocephala sp. is also high, between 4% and 8% of soil mass. Development and selection of Brassica species that produce higher concentrations of isothiocyanate would increase the effectiveness of Brassica biofumigation as an alternative to methyl bromide for controlling soilborne insects.

Cordyceps variabilis has long been erroneously reported to be a pathogen of beetle larvae; studies of newly collected and herbarium specimens revealed that C. variabilis attacks fly larvae, particu...

Adult Podisus maculiventris (Say) consumed no adult ladybird beetles (Harmonia axyridis Pallas) and 30-35% of larval ladybird beetles in no-choice laboratory trials. Nymphal P. maculiventris appeared to be more agile than adults in petri dishes and attacked 65% of both larval and adult H. axyrides; however, they only killed and consumed 50% of larvae and 20% of adult ladybird beetles. Ladybird beetle larvae were aggressive and often escaped, whereas adult beetles were usually rejected by the nymphal predators, suggesting unpalatability. Overall, P. maculiventris took more than four times longer to capture ladybeetle larvae than to capture fall armyworms (Spodoptera frugiperda [J. E. Smith]). In nature, while some ladybird beetles are undoubtedly consumed by P. maculiventris, most probably escape predation, either by evasion or through lack of palatability.

The nematode, Mermis changodudus sp. n. (Mermithidae) is described as a new parasite of Heteronychus beetle larvae (Scarabaeidae) in Madagascar. The diagnostic characters of this species are 1) eggs without polar protuberances or filaments, 2) mouth shifted slightly ventrad and 3) embryo not fully developed at oviposition. This is the sixth species described in the genus Mermis (sensu stricto).

Two occluded viruses of the Entomopoxvirus (D)/ ∗ : ∗ / ∗ : X X : I O (= Vagoiavirus) group have been found in larvae of Dermolepida albohirtum (Scarabaeidae: Melolonthinae) and Aphodius tasmaniae (Scarabaeidae: Aphodiinae) from northern Queensland and northern Tasmania, Australia, respectively. Electron microscopical studies have been made of thin sections of occluded (mature) and nonoccluded virus particles within the fat body tissue of living diseased D. albohirtum larvae and of occluded virus particles within a dead, field-collected A. tasmaniae larva. The morphology and development of the known Australian entomopoxviruses are compared with previously known entompox or spheroidosis viruses from various insects.

SummaryIn tests in which raspberry beetles (Byturus tomentosus) were sleeved on fruiting laterals, fruits of seven Rubus species were less damaged than those of the raspberry (R. idaeus) cv Norfolk Giant. Fruits of F1, or backcross hybrids with R. idaeus of two of these species, R. coreanus and R. crataegifolius, also showed low levels of damage in sleeve tests. In natural field infestations four of these hybrids and other derivatives of the two species showed significantly lower percentages of receptacles damaged by beetle larvae than susceptible controls. In private gardens and in large commercial plots of oneresistant cultivar the highest level of resistance observed would probably obviate the need for spray control.

Occluded viruses of the Entomopoxvirus (D)/ ∗ : ∗ / ∗ :X/X:I/O ( = Vagoiavirus) group have been found in Othnonius batesi (Scarabaeidae: Melolonthinae), Dermolepida albohirtum (Scarabaeidae: Melolonthinae), and Aphodius tasmaniae (Scarabaeidae:Aphodiinae). Diagnostic criteria are given for the virus infections in the respective native host larvae based upon both macroscopic and microscopical observations where possible. The distinguishing characteristics of the virus spheroids and spindles from the three host species are compared with each other and with similar bodies present in other entomopoxvirus infections. Virus-containing spheroids of the O. batesi and D. albohirtum viruses were barely infective at dosages fed to native host larvae in the laboratory, and the disease course of each was prolonged. Cross-infection feeding trials of the D. albohirtum virus in several other melolonthine species larvae were negative.

Daily rates of predation by Podisus maculiventris (Say) (Heteroptera: Pentatomidae) on Mexican bean beetle larvae, Epilachna varivestis Mulsant (Coleoptera: Coccinellidae), were measured in soybeans, Glycine max (L.). The number of Mexican bean beetle larvae attacked per predator per day remained consistently low throughout 2 years of study. Estimates of the area searched by P. maculiventris were calculated from the number of prey attacked, number of prey available for attack, and leaf area. As leaf area increased, P. maculiventris searched more area, demonstrating a search strategy shared with other predators of canopy-inhabiting prey in soybeans.

The potential bacterial mutagenicity of the beta-exotoxin of Bacillus thuringiensis var. thuringiensis was detennined by the Salmollella-microsomal assay (Ames test) and found to be nonmutagenic. The activity of three experimental preparations of B. thuringiensis var. thuringiensis were determined by feeding the preparations to house fly larvae and to neonateColorado potato beetle larvae, Leplinotarsa decemlineala (Say). Comparisons with controls were made as to food consumption and mortality rates, and the LDIOthrough LDQ, were calculated. In field tests of 0.05-ha plots of potatoes, an experimental preparation of B. lhuringiensis var. lhurillgiellsis provided excellent control of the Colorado potato beetle when applied weekly at the rate of 1,892 ml/O.4 ha.

Five formulations of Bacillus thuringiensis var. israelensis (serotype H-14) were evaluated against larvae of eight mosquito species. In the laboratory, most species essentially showed similar levels of susceptibility to a given formulation. The range of activity of the various formulations against a given species was on the order of two- to sixfold. In general, the LC90 against fourth-stage larvae ranged from 0.13 to 0.45 ppm, for high-potency formulations, to 0.45 to 0.9 ppm for low-potency formulations. Second instars were two to six times more susceptible than 4th instars to the various formulations. Under field conditions, the various formulations showed different activity levels. In clear, shallow, and nonvegetated water, the high-potency formulations yielded excellent control of larvae at rates as low as 112 to 280 g/ha. Formulations with low potency were needed at rates as high as 280 to 560 g/ha to yield effective control of larvae in these biotypes. None of the commercial formulations at mosquitocidal and fivefold these rates induced short-term effects on the dominant nontarget fauna. Mayfly and dragonfly naiads, diving beetle larvae and adults, and ostracods were not affected at the rates of 0.56 to 2.24 kg/ha of the formulations employed.

A comparison of mortality, developmental time, and pupal weight was made for Mexican bean beetle larvae reared on three stages of soybeans and reproductive stage lima beans in 12 constant temperature and relative humidity (RH) conditions. At high humidities and favorable temperatures (17, 22, and 27° C) there were no significant differences in survival to the pupal stage on the various host plants. On lima bean foliage, larval survival was not significantly influenced by moisture stress. However, survival decreased on all soybean hosts as temperature increased, or as RH decreased, and was inversely proportional to vapor pressure deficit. These stresses are also reflected in larger development times and lower pupal weights. Survival at 32° C in all cases was low. Female larvae appear to be more capable of enduring conditions of moisture stress than males. Stress due to adaptation to change in RH was also observed.

Larvae of Enoclerus sphegeus Fabricius (Coleoptera: Cleridae) were separated into three groups for study. Throughout their development, the larvae in each group were fed mountain pine beetle larvae, Dendroctonus ponderosae Hopkins (Coleoptera: Scolytidae), of a specific size (small, medium, or large). Clerid larvae fed small D. ponderosae larvae generally completed three stadia, while the other two groups, which were fed medium-sized and large prey, respectively, usually passed through two larval stadia. The number of stadia a larva would have was determined by the amount of food consumed during the first stadium. The feeding period of larvae given small prey was considerably longer than that of those fed medium-sized or large beetle larvae, but the prepupal period was much shorter. The head capsules of second-instar larvae that passed through two stadia were distinctly wider than those of second-instar larvae that completed three stadia.

Summary. 1. A severe attack by a flea-beetle, Psylliodes hyoscyami Linn. on Hyoscyamus niger L. grown as a commercial crop is recorded. 2. The life history and developmental stages of the beetle are described. 3. Suggestions for control are made. 4. The larvae of Lonchaea flavidipennis Zett. (Sapromyzidae, Diptera) has been found associated with the beetle larvae in the damaged stems.

The use of radiography in the study of cryptic insects was investigated for several kinds of forest insect damage. Longwave or “soft” X-rays (5-35 kilovolts) were found most suitable for the detection and study of insects infesting plant material. A portable industrial X-ray unit was used which had an output of up to 35 kilovolts, 10 milliamperes, and variable exposure time. Excellent results were achieved in radiographs of western pine beetle larvae and pupae in ponderosa pine bark; adult gallery construction and larval development of Ips confusus (LeConte) ; red turpentine beetle in situ in sugar pine; buprestids, cerambycids, siricids, and lyctids infesting various thicknesses and kinds of timber; weevils infesting lodgepole pine tips and seed-infesting insects. Less satisfactory was the detection of insects in whole cones, although their galleries could be detected.

The larvae of the Rhinoceros beetle ( Oryctes nasicornis L.) have been the main subject of this investigation. They have proved to have a mode of feeding different from those which are considered true wood-eating beetle larvae (Buprestidae, Lyctidae, and Cerambycidae). Quantitatively comparing food and excreta of the Rhinoceros beetle larvae, we were able to demonstrate a remarkable decrease in both cellulose and soluble sugars, thus proving that the free-living intestinal micro-organisms feed on carbohydrates in the saccus, at the same time increasing the protein contents of the original food to a great extent. After regurgitating these substances into the mid-gut the larvae utilize the micro-organisms as direct protein supply. In the research on the respiratory exchange, larvae of Melolontha melolontha L. were also included. The derived RQ proves fat combustion and low metabolic rates in both species.

The time that should elapse between fumigation treatment and mortality determination is dependent on many factors, among the most important being the nature of the toxicant and the susceptibility of the insect species.

L-canavanine is a highly toxic L-arginine analog found in some leguminous seeds. Larvae of the bruchid beetle Caryedes brasiliensis, collected in Costa Rica, subsist solely on tissues of the mature seed of Dioclea megacarpa, which contains more than 8 percent L-canavanine by dry weight. The arginyl-tRNA synthetase of the bruchid beetle larvae discriminates between L-arginine and L-canavanine, and canavanyl proteins are not synthesized. In this way, bruchid beetle larvae avoid an adverse biochemical effect of L-canavanine.

The life cycle, feeding behavior, and mortality of the larvae of Dendroctonus frontalis Zimmerman (Coleoptera: Scolytidae) were studied under natural conditions in the Georgia Piedmont during the summer of 1975. Four larval stadia had an average developmental time of 5 days each. Instars 1 and 2 make a larval mine, whereas instars 3 and 4 begin and complete a feeding chamber and move into the outer bark to pupate. Larvae mining in perithecial, blue-stained phloem make significantly longer mines than larvae mining in unstained phloem (8.5 mm and 5.2 mm, respectively). For larvae in the lower portion of the bole (2-4 m) a 70.7% mortality occurred between the egg and 1st and 2nd instars, and a 90.4% mortality occurred between the egg and 3rd and 4th instars.

Southern pine beetle, Dendroctonus frontalis Zimmerman, was reared aseptically from egg to adult using in vitro cultured masses (callus) of pine cells taken from loblolly pine. Callus on 3% nutrient agar was the best of the systems tried for producing aseptic beetles in 35–55 days in the complete absence of mycangial fungi. Adult production increased from 14–26% of hatched larvae when β-sitosterol was added to the culture medium.

The excreta of clothes moth larvae feeding on wool contain 0·28 per cent of elemental sulphur. It is probable that this is formed by reaction of sulphides with disulphide bonds during the digestion process. No sulphur was excreted by carpet beetle larvae on a similar diet.

Engelmann spruce trees were frilled by hand hatchet and Silvisar® 510 (dimethylarsinic acid) was added to the frills at periodic intervals before the peak flight. period of the spruce beetle in an effort to produce lethal traps. Some trees were felled at. periodic internals after treatment and some were left standing. An evaluation was made 12–13 months after treatment. Number of attacks in samples from trees treated in mid-June and felled 2 weeks later was not significantly different than that from check trees. However, only a few live spruce beetle larvae and pupae were found in samples from trees treated at this time whereas significant numbers were found in samples from check trees.

Water vapor absorption is compared in the two tenebrionid larvae Tenebrio molitor and Onymacris marginipennis. Thresholds for absorption and "absorption capacity," which depend on ion transport by Malpighian tubules, are consistently different over the entire size range of the two species. Because of lower thresholds, uptake rates of Onymacris are over double those of Tenebrio in larvae of the same size at identical ambient water activities. By contrast, passive determinants of uptake, rectal conductance, and morphometry are similarly scaled with size in the two species. A ventilatory mechanism of vapor entry into the rectum is proposed for both species, since the anal canal is too long and narrow for exclusively diffusional entry. Vapor uptake in relation to larval mass was described by a simple diffusion model through rectal tissue, where flux varied directly with surface area and inversely with the distance between the lumen and Malpighian tubules. Failure of rectal conductance to increase proportionally with body mass means that size-specific vapor uptake declines with larval size in both species.