Bokehlicious

Like may other blippers, I'm participating in a 'Year with your Camera', a free internet course run by Emma Davies. This week's lesson was on aperture, and those with a bit of experience were allowed to skip the basic exercise and undertake aperture-related challenges, including producing a classic bokeh shot. Fortunately the sun appeared for a while, and reflected nicely off the droplets left by yesterday's rain.

In the afternoon I went for a wander round a couple of local villages, finding more interesting walls, one of which had a large population of the spider Amaurobius similis. There's an image of it's tunnel and web in the extra photos. This is one of the spiders that produces cribellate silk, which appears somewhat bluish if you look in large. 


Cribellate spiders comb their silk to a woolly structure. To do this they have a comb (calamistrum) on the metatarsus or the tarsus of the fourth legs and an extra silk producing organ (cribellum) just in front of the spinners, which appears as a transparent plate. The comb pulls the silk out of the cribellum and the silk is combed to a woolly structure. The combed silk is made up of thousands small threads enforced by some thicker ones. There is no glue on the threads but the insect gets stuck with the hairs on their body in the silk. The thicker threads in the silk prevent the insect from tearing the silk.