Identify this!

This is a joke sent to me by a friend.

One day at a local university science faculty. A practical examination of an entomology (study of insects) paper was being conducted. This particular test was a very difficult one. Students were given just samples of several insect's legs and were required to identify the insect's species and names from these samples. Two hours had elapsed but not one of the students were able to identify the insects. One student in particular was very disappointed and frustrated. He decided to leave the examination hall.
"Bammmmmm!!!!" he loudly slammed the door shut on his way out. Upon this, the lecturer inside the hall angrily shouted at him "Hey, who the hell do you think you are, going about slamming doors like that. What is your name ?!!!!!" The student, who was standing on the other side of the door, then stuck only his legs into the hall. Only his legs were visible from inside the hall. He then said "This is my leg sir...... Now, from just looking at my leg..... can you guess who I am?????"

(Hope you enjoyed the joke........ I sure did)