CHELONE MYDAS. 353 



parts there are vast plexuses of veins. The vessels of the oviduct are 

 from those that come to the ovaria, but the upper part is supplied from 

 the brachial ; before they pass out of the shell these anastomose with 

 the ovarial artery on the membrane of the shell. 



The clitoris is a good way from the common opening of the rectum 

 and bladder : it is something like a bird's tongue lying in the lower jaw ; 

 for there are two projections or points from the clitoris, passing as two 

 bodies, like cords, on to the bladder, and seem to be lost there. These 

 two cords make a groove, which becomes wider from the tip of the 

 clitoris as it passes to the bladder. From this groove, two ridges arise, 

 about an inch from the mouth of the bladder, and, as they pass to the 

 mouth of the bladder, encompass it, or are continued into the mouth of 

 the bladder 1 . These grooves are a kind of conductors of urine and 

 eggs. Two muscles are inserted into the root of the clitoris which arise 

 from the pubis : their use seemed to be to fix it and make it less move- 

 able. There is a cavity on the upper part of the termination of the 

 rectum, into the common cavity, as in fowls 2 . 



Of the Eye. — The under eyelid seems to move most, and therefore 

 has less of the scales upon it, and those that are there, become softer 

 the further they are from the edge of the lid ; so that it admits of being 

 folded near the brim of the orbit, and on its inside. In every respect 

 the contrary obtains in the upper lid; for the scales become harder and 

 broader the further from the edge of the lid ; so that the folding of the 

 lid is near the edge, and in the raising of the lid it is pushed out, or 

 swells out. The muscle of the inferior lid is very broad, arising from 

 the bottom of the orbit, the same as in the human subject. The 

 internal surface of the lid is lined with a cuticle 3 . There is a mem- 

 brana nictitans, which is very strong and thick ; it is moved by two 

 muscles, which arise together from the globe of the eye on the inner 

 side of the optic nerve; the common muscle is pretty broad and 

 passes above the nerve, outwards, becoming narrower, and then 

 divides into two distinct muscles, each ending in a round tendon : the 

 lowest is lost in the superior horn of the nictitating membrane, at the 

 external canthus ; while the other continues its course round the optic 

 nerve to the lower part of the eye, and is inserted into the lower horn 4 . 



There are two glands, one at the external canthus, the other at the 

 internal, as in fowls. The external [true lacrymal gland] is very large, 

 about the size of the eye itself, and is of the conglomerated kind, having 

 a wide short duct opening into the external canthus of the eyelid : the 



i [Hunt. Prep. Phys. Series, No. 2719.] 2 [lb. No. 2130.] 



3 [lb. No. 1768.] * [lb. No. 1767.] 



vol. n. 2 a 



