This man used his mother's maiden name (MARCH) when he enlisted, so is "mis-filed" in the WW1 Service Records (WO 363):

(As John March) he enlisted December 1914, declaring age 20y, born Eastwood, Essex.
Served as Pte 021489 with the ASC.
Died in France (influenza) December 1918.

Home address: Lower Hockley Hall, Hockley, Essex;
Parents: Gustav Hugo & Ellen Eliza (nee MARCH, married 1883);
Brothers: Alfred Edward (1886), Frederick Emil (1888), Walter Hubert (1891) & Manfred Conrad (1893);
Sisters: Mrs Mathilde Maude KUMMER (1884) & Ella Jane (1898).

NB: Most of the siblings are referred to by their middle name in the Record.
Hubert is living in Canada in 1919.
Conrad & Ella are surnamed MARCH, so perhaps the whole family changed their surname?
Parents' marriage, Siblings' & father's full names found on freebmd.

Anc****y, MAR, pages 104641-104673