CASE 20.--Margarethe T--, æt. 16, has hypermetropia 2 D. in the right eye, V. 5/6, in the left the ophthalmoscope shows with an otherwise normal condition a higher degree of hypermetropia, with + 6·5 D., V. 1/18, with + 10 D. No. 3·0 is read. No spectacles have been used until now; for the past few years school tasks have been performed with a certain effort, only during the last year the asthenopia has increased. Squint is not present, and with prisms as well as with the stereoscope (by the use of objects, whose size corresponds to the defective sight on the left side) binocular fusion can be proved. The case is the same as regards divergent strabismus. CASE 21.--Mr. H--, æt. 28, has myopia 6 D., V. 6/9 in the right eye; the left eye has always been weak sighted, emmetropia is detected with the ophthalmoscope, with normal fundus, V. 1/18. No squint, binocular fusion can be proved with prisms. CASE 22.--Mr. B--, æt. 47, has hypermetropia 5 D., V. 5/9 in the right eye. Left eye with + 5 D., V. 1/18 (a few letters of 12 also were recognised at 1 m.). It seems, however, that the patient is not able exactly to indicate the position of the retinal images of his left eye, he does not know, as he expresses himself, "whether the letters stand here or there." Patient observed the defective sight long ago; the ophthalmoscopic condition is normal. Patient really comes on account of his son, aged 7-1/2, in whom hypermetropia of 3·5 dioptres is detected with the ophthalmoscope, right eye with + 3·5 V. 5/9. Left eye has convergent squint, V. 1/36, No. 3·0 is read with + 6·5 D. The hereditary tendency is seen also in the following case: CASE 23.--Mrs. S--, æt. about 46, on the left H. 4 D., V. 5/18 to 5/12, has used no spectacles until now, and reads No. 0·75 without glasses at about 15 cm. R. with + 4 D., V. 1/18, with + 6·5 D. large letters of No. 5·0 are recognised. Two sons, present at the same time, are hypermetropic. One has in either eye V. 1/4, the other a slighter degree of congenital amblyopia. CASE 24.--Johanna L--, æt. 4, came under treatment for a congenital fibroma covered with hair, about the size of a cherry-stone, situated on the outer corneal margin of the left eye, which was removed. Three years later, when the child had learnt to read, emmetropia and full visual acuteness was observed in the right eye, with the left No. 4·0 only is read with difficulty. The ophthalmoscope shows a slight degree of irregular astigmatism of the cornea, which in no way explains the defective vision; the image of the fundus is perfectly clear and quite normal.