seen in many, if not most micro image of Meridiana rocks. For example, from the most recent scan, in the crack near the sphere, and a little bit above the sphere, many of these short, clumping, dark filaments can be seen. There are better examples from older micros. These seem to be on the surface and have a preference for overhangs and shadows. The resolution is not good enough for much detail, but they seem to be on the rock, not just shadows in it. Even if they are part of the rock, what are they? Animal, vegetable or mineral. Can't tell without an SEM, but pretty suspicious to me.

Another interesting feature seen recently is the possible vascular structure within a sphere. In this image, 1/3 from the left and 1/4 from the top, there is what I believe is an old eroded sphere. It has some pits in it, and an apparent short cylindrical structure extending from near the middle. If this was the only example of this, I would not point it out. It is, however, one of several examples that seem to show something like vascular bundles within the spheres. These are uncommon, but have an appearance like a sliced tomato. This example is more eroded than previous, so the central stem sticks out more. I would surmise that preservation of these fine internal features was uncommon. The vast majority of the spheres have a uniform, granular texture, and I have seen no evidence of any internal layering.