  Magnetic properties of a polycrystalline alloy Ni$_{2.19}$Mn$_{0.81}$Ga,
which undergoes a first-order magnetostructural phase transition from cubic
paramagnetic to tetragonal ferromagnetic phase, are studied. Hysteretic
behavior of isothermal magnetization $M(H)$ has been observed in a temperature
interval of the magnetostructural transition in magnetic fields from 20 to 100
kOe. Temperature dependencies of magnetization $M$, measured in magnetic fields
$H = 400$ and 60 kOe, indicate that the temperature of the magnetostructural
transition increases with increasing magnetic field.
