This is a good text i found describing the Simian Line. Most hands have three easily noticeable lines, the earth (life), which runs around the ball of the thumb and two transverse lines, the water (heart) and air (head) lines. A simian line occurs when the water and air lines fuse and join, to become one transverse line only across the palm. The name simian line originates from Latin simia, meaning ape. Yet interestingly, the association is inaccurate as, like humans, the hands of monkeys and apes have more than one transverse lines, without any simian line formation. In chirology the meaning of this marker relates to character traits but it also has significant scientific relatedness to medical chromosomal disorders such as Down’s syndrome. Apparently around 55% of people born with Down’s Syndrome have this lineal formation. Our water lines relate to what we feel, and our air lines, to what we think. The impression here is that the functions of feeling (wate...