This is not your typical electron microscope snowflake photo, usually delicate and beautiful. It's a capped column snowflake zoomed in 50,000 times. Those intriguing and sightly gross flabby little hair thingies on both ends of the flake are rime ice.
Rime ice forms on snowflakes "under some atmospheric conditions, forming and descending snow crystals may encounter and pass through atmospheric supercooled cloud droplets. These droplets, which have a diameter of about 10 µm (0.00039 in), can exist in the unfrozen state down to temperatures near −40 °C (−40 °F).
Contact between the snow crystal and the supercooled droplets results in freezing of the liquid droplets onto the surface of the crystals. This process of crystal growth is known as accretion. Crystals that exhibit frozen droplets on their surfaces are referred to as rimed. When this process continues so that the shape of the original snow crystal is no longer identifiable, the resulting crystal is referred to as grapple.