It might be thought that the simple and obvious way to ascertain whether a couching had been done would be to ask the patient or his relatives. In a large number of cases this is of course sufficient; but in India, at all events, there are many who will deny the operation they have undergone. This is due to the fact that it is widely known among the people that the British surgeons view the coucher and all his methods with extreme disfavour. Patients are therefore reluctant to admit having consulted him, and they also are afraid lest treatment should be refused them, once their true history is known; for it is common knowledge amongst them that the Western practitioner is extremely reluctant to interfere with an eye which a coucher has spoilt. It is well, therefore, to consider carefully the grounds on which the physical diagnosis of a couched lens should rest. We will first consider the case of those eyes in which =the cataract has been definitely removed from the neighbourhood of the pupil=. These present certain well-marked signs: (1) _The pupil is brilliantly black_, and (2) _the plane of the iris is flat_. It may seem strange to insist upon these points, but to the trained eye they are so obvious that a diagnosis can often be made, as soon as the patient takes his seat in the out-patient room, in front of the surgeon. The quality of the blackness of the pupil is difficult to put into words, but it arrests the attention by its contrast to the ordinary appearance of the pupil in people so advanced in life as the subjects of cataract usually are. The phenomenon is due to the whole cataract, capsule and all, being thrust away from the pupillary area, and it can be equally well seen in cases which have undergone the intra-capsular operation. Then, with regard to the flattening of the iris, the trained eye is used to the appearance presented by the slight forward convexity of that membrane as a result of the presence of the lens behind it; whereas the complete removal, not merely of the lens, but also of the support of the suspensory ligament, makes the iris flatten out in its own plane.