Gall of the week is back after a technical issue. It is the fungal gall of Claviceps purpurea otherwise known as ergot, on many grasses and cereals. It is the cause of St. Anthony's fire mania if consumed in contaminated flour. Photographer unknown.

And the agamic generation galls of Neuroterus quercusbaccarum.

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Gall of the week, well two actually. A chimera with the cynipid galls of Andricus kollari/infectorius f. agamic agg and A. aries f. agamic growing in close proximity on oak Quercus spp. Photographer unknown.

Gall of the week is a fungal gall which at first sight might be taken for an invertebrate gall, although the there is a larger protuberance on the underside of the leaf. It is caused by Exobasidium vaccinii on cowberry, Vaccinium vitis-idaea. Photo by Mike Poulton.

Gall of the week is caused by the midge Jaapiella veronicae on speedwells, Veronica spp. According to Skuhrava and Skuravy in 'The Gall Midges of Europe' this is the commonest gall midge in Europe. Photographer unknown.

Gall causer rather than gall of the week this time. A sexual generation female of the cynipid wasp Trigonaspis megaptera which causes galls on oak trees, Quercus spp. Photo by Michael Chinery.

Gall of the week is caused by the psyllid Trichochermes walkeri on buckthorn, Rhamnus carthatica. Once vacated by the causer the gall is often home to aphids. Photo by Graham Calow.

Correction this is a psyllid not a scale insect.

Gall of the week is I think that of the scale insect Pachypsylla celtisdismamma on hackberry, Celtis occidentalis, in North America. Photo by Peter Shirley.

Gall of the week, one for our North American friends, is caused by the cynipid wasp Diplolepis triforma on the rose Rosa acicularis. Photo from Sudbury Ontario by Peter Shirley.

Gall of the week is caused by the weevil Rhinusa antirrhini on common toadflax, Linaria vulgaris. Photographer unknown.

Gall of the week, found in @britgalls garden this week, is the sexual generation currant gall of the cynipid wasp Neuroterus quercusbaccarum on oak Quercus sp. Photo by Peter Shirley.

Gall of the week is unusual looking mistletoe, Viscum album. It's host tree has died so it has changed to autumn colours!

Gall of the week, easy to find now, is caused by the mite Phyllocoptes goniothorax on hawthorn, Crataegus monogyna. Photo by Tom Higginbottom.

Gall of the week is caused by the gall midge Putoniella pruni on Prunus spp. especially blackthorn P. spinosa. Photographer unknown, please say if it is you.

Gall of the week is caused by the psyllid Trioza flavipennis on ground elder, Aegopodium podagraria. Photo by Roelef Jan Koops.

Gall(s) of the week. These were collected duting a walk in South Africa many years ago, but britgalls has no idea what species the causers are, beyond likely mites and midges. Feel free to suggest candidates.

Gall(s) of the week. A photo taken many years ago of galls collected in South Africa. No idea what the species are that caused them, beyond probably mites and midges. Feel free to offer suggestions.

Gall of the week, coming to an oak tree near you soon, oak apples, caused by the cynipid wasp Biorhiza pallida. And a reminder that Oak Apple Day is May 29th. Photograph by Mike Poulton.

Gall of the week still, easy to spot before the leaves appear, is the cynipid caused gall of Andricus curvator agamic generation on oaks, Quercus spp. Photo by Jenny Seawright.