The son of Rep. Mervyn Dymally surrendered to begin serving a one-year jail sentence for firing a gun into a Wilshire District duplex during an argument with his wife. Mark Steven Dymally, 31, pleaded guilty last Oct. 10 to two felony counts in connection with the incident in December, 1985. Authorities said he became angry when his wife refused to leave a male friend's house and later fired several shots into the front and rear of the building. In addition to the jail sentence, Dymally was placed on three years' probation and ordered to pay $22,000 in restitution. His father represents a district that includes Compton and South Los Angeles.