United States
The Doctor of Juridical Science, J.S.D. (or S.J.D.),sometimes awarded as Doctor of the Science of Law, is the highest law degree awarded in the United States. Because of its rarity, most law schools in the United States accept the LL.B./J.D. degree as the basic entrance qualification for law school teaching. Laws schools that place an emphasis on legal scholarship have more professors holding advanced law degrees such as the the LL.M. or the J.S.D./S.J.D.
Source: Answers.com
A person who studies and practices law is typically referred to as a lawyer or an attorney.
You call someone that studies metal a metallurgist.
A physicist.
a person who studies planets is a planetologist.
Student
florist
An Anthropologist.
Microbiologists
Brocollogist
A Zoologist
malacologist
A physicist.