The second picture denotes a rabbit and is very clear. Semiotics means that you are able to make your message clear to your viewers. It means that there is a clear path of communication between the meaning of your message between the two of you. With this theory that we can interpret solid shapes better, it makes semiotics easier to understand.
Picture Citations: http://joasdi.nl/joasdiart/?tag=pencil-drawing
and i cant find the other one!