CARINATjE 



Alciformes 



Puffin. Fratercula arctica. Plate XV. 



The eyeground is red and rather uniformly stippled with small, 

 mixed light-red and dark-gray dots. Above the upper end of the 

 optie disc and towards the temporal side is a small, round, red area 

 surrounded by a pale, light -gray film, shot with bright lines on the 

 outer and inner margins — doubtless the macular region with its 

 central fovea. Head noticed that not only this area but most of the 

 upper half of the fundus is very sensitive to light. The optic papilla, 

 oblong, narrow and with a rounded upper extremity, lies low down in 

 the eyeground, while the pecten extends well forward and behind the 

 lower margin of the pupil. A view of the nervehead is much ob- 

 scured by the body of the massive pecten which almost covers it when 

 seen, as with the mirror, from above downward. The small seg- 

 ment visible with the ophthalmoscope appears not brilliant white 

 but rather a bluish-white, the margins of the pecten being covered 

 with black pigment. 



Extending at right angles to the disc on both sides are a few very 

 fine, gray opaque nerve fibres that finally disappear in the fundal 

 periphery. The pecten is of the usual chocolate-brown color and 

 comes well forward towards the lens, especially in its inferior aspect. 



Lariformes 



Great Black-backed Gull. Larus mart nits. Plate XVI. 



The general coloration of the eyeground varies from a dull gray 

 to a dull brown — mostly the latter — traversing which are many 

 reddish choroidal vessels running more or less in a vertical direction. 

 It is the number and visibility of these capillaries that give the red 

 tone to an eye-ground essentially gray. 



The optic disc is a long, narrow oval, quite white, with a quan- 

 tity of fine gray lines radiating in all directions from the papillary 

 margin. On the inner aspect of the eyeground the macula is seen. 

 It is situated about one disc-length from the upper extremity of the 

 pecten and half a disc-length above the end of the same organ 

 on the inner side. The macula resembles a blue-green flake of iri- 

 descent glass. It is of oval shape with a reddish-brown center, 

 which, however, is unprovided with a reflex ring. 



The pecten appears to be in folds; the lower, or broader portion 

 extends well forward towards the lens and turns towards the nasal 

 side of the bird's head. The inner quadrants of the fundus are more 

 easily seen with the ophthalmoscope than the outer half but, so far as 

 the latter area is visible, there is no sign of a second macula on the 

 outer part of the eyeground. 



134 



