That dynamic astigmatism of the lens may exist has been recognized since Donders published his classical work in 1864, and it is now generally conceded that an unequal contraction of the ciliary muscle may exist, producing irregular curvature of the crystalline lens and often producing a sensation like that attending accommodation for the punctum proximum , with its accompanying fatigue and asthenopic symptoms. This astig matism has often been observed in practice as sociated with corneal astigmatism, which it modifies in various degrees, sometimes increasing, sometimes partially, sometimes fully, and at other times over-correcting it. Owing to a cessation of this action as a result of loss of accommodation from age or from the use of mydriatics, corneal astigmatism that had previously been concealed, becomes manifest. Or what had appeared to be a myopic astigmatism may be shown to be a hyperopic corneal astigmatism. The question as to whether this dynamic