What is this??

found this on my dogs side,what is it?  

Hello - I'm afraid that the first rule of lumps is, that you cannot expect (there are some exceptions) to identify a lump with any certainty from its visual appearance, especially out of context from the rest of the dog.  There are some excellent articles available should you type 'lump' into the search-bar of the blog, but essentially your vet will take a look in context of the patient's signalment (who / what breed / age etc they are) and history (clues about lifestyle, development of the disease etc) to work out what it is most likely to be and will often propose some kind of test, often including a cell or tissue sample to see if that is correct.  To me at this angle, this one looks like a lump rather than a tick and is quite dark; put of context I can't rule anything  out from a melanoma to a dark skin tag, small hernia or accessory nipple.  Your vet, however, is well equipped to advise you;  wishing you all the best of luck with your appointment and please let us know how you get on moving foreward.