Total and differential haemocyte counts following repeated haemolymph withdrawals were made in V instar larvae of P. demoleus. While total count showed a steady reduction reaching its lowest in prepupal stage, much variation was observed in the relative percentage of various cell types. Further, the repeated removals of haemolymph from V instar larvae and pupae affected imaginal moulting and le...

20-Hydroxyecdysone, the arthropod moulting hormone, was biotransformed by the fungus Curvularia lunata NRRL 2178 to the rare ecdysteroid, 2-dehydro-3-epi-20-hydroxyecdysone, and the novel 3alpha,9alpha-cyclo ecdysteroid analogue, (20R,22R)-3beta,14alpha,20,22,25-pentahydroxy-3alpha,9alpha-cyclo-5beta-cholest-7-en-2,6-dione in 14 and 44% yields, respectively. Ponasterone A and pterosterone were ...

Insects that live in the interior of caves show the basic internal temporal organization of coupled oscillators. An analysis is made of the coupled moulting and oviposition cycles of Folsomia candida, a cave-dwelling Collembolan, with regard to their oscillatory nature, their phase dependent responses to external perturbations, the effect of coupling on these responses, and conjecture about the...

Electrical activity of the brain of Lithobius forficatus has been recorded. The addition of ecdysteroids (moulting hormone) in the haemolymph increased the frequency and amplitude of electrical response. Such a stimulation might be specific to these products since cholesterol and juvenile hormone had no action. The destruction or removal of various parts of the cephalic endocrine system demonst...

A new genus Dimorphacanthella is established for Tetracanthella anommatos Chen and Yin, 1984 and Dimorphacanthella mediasetasp. n. from China. The new genus exhibits an unusual metamorphosis: small juveniles, previously called Uzelia anommatos Yue & Yin, 1999 get the second pair of anal spines resulted from moulting and become "Tetracanthella". Species identity of forms with two and four anal s...

A convenient synthesis of inokosterone, pterosterone and 24-epi-pterosterone has been accomplished. The former ecdysteroid exists as two C-25 epimers and could be separated from each other through their diacetonide derivatives. Each of the C-25 epimers has been subjected to moulting hormone activity testing using the Musca bioassay and it was found that the less polar isomer, inokosterone "epim...

Larvae of the flesh-fly, Sarcophaga bullata, were injected with the synthetic moulting hormone ecdysterone or saline at the beginning of the third and final larval instar. One group was left untreated. The ecdysterone-injected larvae showed an increase in number of secondary lysosomes in the midgut epithelial cells similar to that observed at the onset of metamorphosis, an event which would nor...

After the antennae of Lithobius forficatus were amputated, electrical stimulation of the deutocerebral apex (= antennal lobes) either in the spring or the autumn led to (1) a decrease in the number of regenerated articles, and (2) an increase in the time-lag between the experiment and moulting. Moreover, in the spring experiments, the antennae regenerated asymmetrically. The electrostimulatory ...