In mid January, in the heat of an Australian summer, a St Andrew’s Cross spider built her web outside my window.

The photo shows the underneath of the spider, a few blobs of dead insect matter, and the characteristic thickened web lines radiating out from the spider’s legs. This cross-shaped formation is what gives the spider its name.

A few days after she arrived, she created an egg sac in the corner of the window sill. The sac was about the size of the top part of my finger, and had an unusual spoon shape. I wasn’t sure what it was — maybe some form of wasp nest? I didn’t really want one of those just outside the window, which is always open in the summer heat, so I moved the little sac down into another part of the garden.

The next day, another egg sac appeared, looking exactly the same as the first one. I decided it must belong to the spider, who had now moved her web even closer to the egg sac. So I let it be.

Here it is from a different angle:

Two weeks later, the spiders hatched! I saw them for the first time early one morning. A cloud of baby St Andrews Cross spiders, just hatched, glowing in the early sun:

The mother hung above on her web, silhouetted against the rising sun:

Evidently the mother will eat the babies if any of them strays onto her web. She’s also partial to chomping off a leg or two from the male spider while mating.

Nine hours later, it was mid afternoon and the sun had moved off the web. The babies had clumped together in a different pattern:

Early the next morning, the cloud-like formation was back. There was still a bit of clumping, though, as shown by the shadows:

It’s a little like a slow-motion kaleidoscope!

The next day, all the little ones were gone, leaving behind an empty shell of an egg sac. Baby St Andrew’s Cross spiders travel by floating away on a strand of silk.

The mother is still at my window, safe and sound.