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wards towards the ciliary ligament. They arise at the pupillary edge, 

 each hy two or three fine twigs, which quickly meet in a common 

 trunk, or sometimes run separately as far as the outer half of the 

 iris, where they unite in a common trunk. 



The deep layer consists almost entirely of a fine network belong- 

 ing to the radiating muscular fibres, and presenting a close analogy 

 with the fine vessels supplying striated muscular fibre ; the vessels 

 being very minute, and the meshes elongated in the direction of the 

 fibres. Sometimes the vessels from this layer unite into a small 

 ramuscule, which empties into a radiating vein ; at others they unite 

 in a common trunk, passing beneath the ciliary ligament into the 

 choroid. 



The movement of the blood in the veins is generally not too rapid 

 to distinguish the direction of the current and the separate globules, 

 which appear to be constantly springing from around the edge of the 

 pupil and pouring outwards along the veins of the iris into the cho- 

 roidal and ciliary vessels. 



When the pupil is contracted, the radiating vessels are rectilinear ; 

 but when it dilates they become curved and bent into zigzag and 

 spiral forms, which are more or less curved or obtuse in proportion to 

 the degree of dilatation of the pupil. This change in the form of 

 the vessels does not appear to produce any difference in the speed of 

 the current of blood. 



Around the ciliary ligament are two and often three circular vessels, 

 receiving the blood from the conjunctiva of the cornea and sclerotic, 

 partly from the iris, and probably from the ciliary processes. Two 

 of them are venous, and empty themselves into four large veins, 

 corresponding to the anterior eiliaries, which arise in a perpendicular 

 direction, and after following a rectilinear course over the sclerotic, 

 finally end in the ophthalmic vein. The third circular ciliary vessel 

 is of an arterial nature, as shown by the greater thickness of its 

 parietes and the rapidity of its current. 



The current of blood in these vascular circles is a most interesting 

 object from the variety of its course, as into each anterior ciliary vein 

 the blood is. seen pouring out from the circular vein in two opposite 

 currents, to be united into one in the larger vessel. The author also 

 describes the appearance presented by the blood poured into the 

 circular veins by their afferent vessels. 



