Assuming you're talking about the development of a foetus inside the womb - the arms usually start to form first (or 'bud' from the body) - this is shortly followed by the leg buds.
Most of the time the back legs start growing first. I have raised a couple hundred tadpoles, and I think every time the back legs were first.
packs of crayons spiders legs ... octopus's arms ...
First the cut off their arms and legs then they eat them
2 arms and 2 legs
How about Legs and Arms.
A cyclops with no arms or legs
2 arms and 2 legs
Giraffes have four legs, but no arms.
Two arms and two legs.
An "extremity" refers to your limbs (arms and legs). Lower extremities are your legs; upper extremities are your arms.
There are many things that can be brown and have no arms or legs. A snake can fit this description, it has no arms or legs and slithers around. Some worms are brown and do no have arms or legs.
The name Brachiosaurus comes from the Greek words "brachion" meaning arm and "sauros" meaning lizard, because its front legs are longer than its hind legs, giving it a unique posture resembling a lizard with long arms.