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HENRY LAURENS AND J. W. WILLIAMS 



of the nuclei is outside the membrane (fig. C) . In young adults 

 the general shape of the nucleus is the same as in the larvae, 

 though the corners are slightly more rounded. The large oval 

 nuclei in the second row belong to the cones. 



The cones are of three kinds. On the edges of the retina 

 particularly, but scattered here and there through it, one finds 

 large, stout cones, with a very short myoid and a bellied out 



Fig. C A portion of the retina of a light eye, showing the visual cells with 

 their nuclei, four rods, three single small cones, and one double cone. 



inner segment with a clear ellipsoid and an oil drop. The 

 outer segment is short and conical. The typical cone is much 

 smaller, and has a longer, more slender myoid, a clear ellipsoid 

 and an oil-drop in the inner segment. This type of cone is always 

 single. The third type is one that is always, as far as can be 

 ascertained, united with one of the first type to form a double 

 cone. It differs from the small cone described in having a much 

 onger myoid. The nuclei of the larger element of the double 



