LXXXVI BOWMAN LECTURE. 



but whereas in senile and presenile cataract as a whole 

 there are more females than males,"* the reverse occurs 

 in lamellar cataract. I have been able to collect, through 

 the kindness of several friends in various parts of the 

 United Kingdom, with the assistance of Mr. J. F. 

 Cunningham at Moorfields, and from published sources, 

 the particulars as to sex in 1887 subjects of lamellar 

 cataract,t and find 1166 males to 721 females. Although 

 the excess of males varies greatly in different batches it is 

 present, little or much, in practically every separate 

 return ; in a few lots the sex numbers are equal, or 

 nearly so, and in only one is there an excess, and that 

 merely nominal, of females. J 



Isolated cases of lamellar cataract, usually of larger 

 size than in the hereditary cases, are of course common 

 enough, and the same is true of other forms of so-called 

 congenital cataract. Although we may feel sure that 

 some of these would have furnished pedigrees if they 

 could have been followed up, there is at present little 

 doubt that such single specimens may often arise inde- 

 pendently of hereditary influence, and be due to some 

 nutritional defect confined to the individual. 



I will refer next to the form of hereditary cataract 

 that Mr. Gunn has named " coralliform," in which the 

 principal opacities radiate forwards from the central 

 part of the lens, ending anteriorly in expansions that 

 appear to be tubular, and remind one of the separate 

 "mouths" of a madrepore coral. Mr. Treacher Collins 

 conjectures that these tube-like opacities lie in the planes 

 of suture between the lens-fibres. || I published a large 

 pedigree of this form of cataract in 1905^[ ; another 



* Nettleship, R.L.O.H., xvi. 

 f See Appendix II. 



\ The numbers in the separate returns are given in Appendix II. 

 Gunn, T.O.8., xv, p. 119. 



|| Treacher Collins, "Developmental Deformities of the Crystalline 

 Lens/' loc. cit. 



f Nettleship, R.L.O.H., xiv, p. 218, Case 58 (Betts). 



