By Mohamed Abdellah

CAIRO, June 8 (Reuters) - Muslim scholars in Egypt on Sunday criticised aspects of a new law on children approved by parliament on Saturday against the opposition of the socially conservative Muslim Brotherhood.

The scholars said the legislation went against Islamic law by allowing women to register children under their own family names and by setting 18 as the minimum age for marriage.

Under the previous law, children had to take their family name from their father, even if his identity was in doubt.

A separate law, which remains in force despite the new legislation, allows girls to marry at 16 and men at 18. In the countryside some girls still marry at a younger age.

Mohamed Mukhtar al-Mahdi, chairman of the Sharia Associations, which runs many Egyptian mosques, said naming children after their mothers was unacceptable because it was in direct contravention of a Koranic verse.

The verse reads: "Call them by (the names of) their fathers: that is juster in the sight of God." It continues: "But if you do know not their father's names, then they are your brothers in faith."

Mohamed Ra'fat Osman, a scholar at the Azhar religious university, said that the ban on marriage under the age of 18 could not stand from the point of view of Islamic law.

"Islam allows marriage at any suitable age, provided the person seeking marriage has the means and his circumstances enable him to form a family," he added.

Osman, a member of the powerful Islamic Research Institute, added: "The people who drafted this law are trying to transfer Western culture to the Islamic world regardless of whether this culture is suitable to the Islamic religion, customs and traditions."

Another Azhar scholar and teacher, Abdullah Samak, said he objected to any implementation of the law that prevents parents from disciplining their children, physically if necessary.

The law allows for six months in prison for parents who harm their children or do not treat them with dignity.

The law also contains a ban on the widespread practice of cutting the genitals of girls, sometimes known as female genital mutilation, with a maximum penalty of two years in jail.

An existing law bans the practice, which is favoured by some clerics but opposed by the religious establishment.

Members of the Muslim Brotherhood, the main opposition force in parliament with 87 of the 454 seats, spoke against these and other aspects of the new law during the parliamentary debate. (Reporting by Mohamed Abdellah, Writing by Jonathan Wright)