I say jack russel terrier... or some type of terrier
I found information on how to determine a dog's breed...
How to Determine a Dog's Breed
Step
1
Look carefully at the size of the dog first to begin to eliminate specific breeds. Determine the dog's color and hair length; this characteristic will be broken into either long hair or short haired.
Step
2
Determine the overall energy level of the dog whether it is playful or fairly sedentary. Observe whether the dog is friendly or aggressive to strangers. Also, notice how the dog reacts to other animals, especially other dogs. This behavior could help identify breed as well.
Step
3
Figure out the dog's build. Decide if it is muscular, small, medium or very small. Then feel the coat of hair on the dog, and list if the fur is wavy, straight, silky or sparse. Write down your assessments of the dog.
Step
4
Pay special attention to the color combination of your dog. Most dogs are colored with a mix of white, black, tan, brown and sometimes red. Next, study the dog's head to determine if it is round, flat or square; also pay special attention to the dog's snout and whether it is long or short.
Step
5
Note whether the dog is very vocal or fairly silent. Many dog breeds have specific vocal cues. You can also look at the dog's tail as another indicator.
Step
6
Write down as many observations about your dog's appearance as possible and get a book or web reference on dog breeds. Use your observations to single out breed possibilities to help determine the specific breed. Be aware that your dog could be a mixture of different breeds.
Here's the website for more information!!
http://www.ehow.com/how_2098578_dete...paign=yssp_art