BOWMAN LECTURE. CXX1X 



in two sibships of cousins and once or twice in an uncle. 

 The total number of affected persons I have been able to 

 find recorded, including the fifty-two collected by Grunert 

 in 1903* is eighty-four, including single cases without 

 family history. Whether we consider this grand total, or 

 only the instances of family prevalence, we find consider- 

 ably more males than females with the disease with no 

 corresponding excess of males amongst the healthy. 

 There is, in the small series collected hitherto, a decided 

 prevalence of consanguinity of parents. Mental defects 

 have been relatively frequent either in the subjects of the 

 disease or in collaterals. In these broad general characters 

 the disease reminds us of retinitis pigmentosa indeed, in 

 one of my cases typical pigmentation of the retina was 

 actually present,t and another case J one was tempted 

 to interpret as transitional between the two conditions ; 

 but the non-progressive character of the present affection 

 appears to constitute an absolute difference. 



No case has been examined post-mortem ; Galezowski, 

 who published one of the earliest of the modern cases 

 (1868), conjectured that the seat of the disease lay in the 

 cones, and Grunert, working on much larger clinical 

 material and by improved methods, also sums up in favour 

 of cone-blindness. It is interesting to note in this con- 

 nection that Stock believes he has microscopical evidence 

 that the bacillary layer is the first part to undergo visible 

 change in retinitis pigmentosa. 



My first case (shown in Fig. 61), was so striking that 

 as the disease seems still to be but little known, I venture to 

 quote it from the paper in which it appeared almost thirty 

 years ago.|| This patient, an intelligent, fairly educated 

 woman, aet. 25 years, came to St. Thomas's Hospital in 1879, 

 with one of her sisters, who was affected like herself. 



* Grunert, A.f.O., 1903. 

 t Fig. 185, Appendix VII. 

 J Miss A, T. 0. S., xxviii, p. 86, Case 9. 



Stock, Heidelberg Congress, 1906 (published 1907) p. 48, and Klin- 

 Mon.f. A., xlvi, p. 226, 1908. 



|| Ht. Thomas's Hosp. Repts., 1880. 



