Avoidance of the host immune response by a generalist parasitoid, Compsilura concinnata Meigen

Abstract.  1. Ecological interactions between parasitoids and their hosts are extremely strong as parasitoid offspring rely entirely on an individual host to complete development. The ability of a parasitoid to use a host is influenced directly by the degree to which the parasitoid can overcome host defences and grow within the host.
2. Hymenopteran parasitoids have evolved different host-specific strategies to defeat the host immune system, such as the use of venom, endosymbiont virus, or mimicking the host tissue. Dipteran parasitoids from the Tachinidae family do not use these subterfuges and rely mainly on avoiding the host immune system by hiding in specific tissues.
3. Little is known of the effect of this strategy on the host immune system, the absorption of nutrients by the parasitoid larvae, or the implications for parasitoid host range.
4. In this study, the impact of a polyphagous tachinid parasitoid Compsilura concinnata Meigen on a pest lepidopteran Trichoplusia ni Hübner are assessed. Phenoloxidase levels and haemolymph proteins were measured in parasitised T. ni as a function of host immune response.
5. Haemolymph phenoloxidase in the host did not vary with parasitisation but was triggered when a piece of monofilament was implanted in the haemocoel. Haemolymph proteins were depleted in heavily parasitised T. ni .
6. These results indicate that C. concinnata has a strategy that avoids the host immune system, and accesses the necessary nutrients for larval growth. This strategy could explain the success of this tachinid and its wide host range.     

The orthopteroid insects described by Linnaeus,with notes on the Linnaean collection

A list is given of the recently recurated Orthoptera s.l. held by the Linnean Society of London. The status of specimens in the collection is evaluated, eight lectotype designations are made, and the orthopteroid species described by Linnaeus are listed alphabetically.     

Antigenic Differences Among Epimastigotes,Amastigotes and Trypomastigotes of Trypanosoma cruzi*

Antigenic differences were demonstrated among trypomastigotes, amastigotes, and epimastigotes of Trypanosoma cruzi by the indirect fluorescent antibody method. Tests using cross-absorbed sera were included in the study.     

Separate Factors in Phytohaem-agglutinin induce Lymphotoxin,Interferon and Nucleic Acid Synthesis

PHYTOHAEMAGGLUTININ (PHA) has many different biological activities, for example, erythroagglutination¹, leucoagglutination¹, stimulation of RNA and DNA synthesis¹ and induction of interferon¹ and lymphotoxin (LT)². We demonstrate here that the induction of interferon and lymphotoxin by PHA is caused by factors separate from those stimulating nucleic acid synthesis.     

The use of sieving during standard pollen pre-treatment of samples of fossil deposits to enhance the concentration of large pollen grains

Small pollen grains and fine particles of the organic matrix in samples of a coarse detritus mud and a blanket peal deposit were removed by sieving through 30μ polyester mesh after digestion with KOH and acetolysis during standard pollen pre-treatment. The technique enhanced the number of large pollen grains m the sample. There was also an increase in the range of taxa which produce huge grains. The method provided a means of estimating the ratio of any scarce large pollen grain to the total grain sum in samples prepared by standard methods of pre-treatment.     

Eurycea bislineata (Green), the Two-Lined Salamander, a New Host of Myxidium serotinum Kudo & Sprague, 1940 (Myxosporida, Myxidiidae)

SYNOPSIS. Myxidium serotinum was found in 51 of 58 (87.9%) specimens of the two-lined salamander, Eurycea bislineata , from West Virginia. This constitutes a new host record. No specimens of the order Salientia, or other species of the order Caudata were infected. Eurycea bislineata appears to be the normal host of M. serotinum , which is specific for the gallbladder in a variety of amphibian hosts. Apparently, larval E. bislineata becomes infected with M. serotinum , and the parasite does not become a mature trophozoite until after the tadpoles metamorphose to the adult salamander. Certain host hormonal factors may be important to the maturation of M. serotinum.     

The Effect of External Conditions on Coremium Production in Paecilomyces farinosus Bainier

Paecilomyces farinosus grew and produced coremia under laboratoryconditions on media containing wide ranges of carbon and nitrogensources. The fungus tolerated higher concentrations of complexcarbon and nitrogen sources than of simple ones. Sustained lowconcentrations of simple carbon and nitrogen nutrients favouredcoremium production. Once P. farinosus colonies had consumedsufficient nutriment, coremium production could take place withoutfurther access to external nutrients. Light was essential for initiation and development of coremia.The tips of the coremia were photosensitive throughout theirgrowth. After growth in darkness during the initial trophicphase of development, P. farinosus required exposure to lightfor at least 8 days before coremia were initiated. The isolate used produced non-coremial strains spontaneously.These usually also lacked the orange, alcohol soluble, pH sensitivepigment found in the coremial strains.     

Characterization of the Malaria Pigment (Hemozoin) from the Avian Malaria Parasite Plasmodium lophurae*

SYNOPSIS. Plasmodium lophurae hemozoin (malaria pigment) is a heme-containing protein which is distinctly different from hemoglobin and hematin by immunologic, spectrophotometric, fingerprint, heme-iron, gel filtration, and starch gel electrophoretic analyses. The calculated average molecular weight of P. lophurae hemozoin is ca. 40,000. Hemozoin contains at least 3 antigenic components and shows some indication of cross-reaction with hemoglobin.