PARAMETER DEGENERACY IN MODELS OF THE QUADRUPLE LENS SYSTEM Q2237+0305

The geometry of the quadruple lens system Q2237+0305 is modeled with a simple astigmatic lens: a power-law mass distribution: m similar to r(beta) with an external shear gamma. The image positions can be reproduced with an accuracy better than 0.01 arcsec for any 0.0 less than or equal to beta less than or equal to 1.85 and the corresponding value of gamma=0.1385-0.0689 beta. This is a factor of similar to 4 more precise than what can be achieved by the best constant M/L lens models [Rix et al., AT, 104, 959 (1992)]. The image intensity ratios and the time delay ratios are almost constant along our one parameter family of models, but the total magnification varies from 8 to >1000, and the maximum time delay (between leading image B and trailing image C) for H-0 of 75 km s(-1) Mpc(-1) varies from more than 20 h to about 1.5 h, while beta increases from 0.0 to 1.85.