CORRESPONDENCE 01? RAY. 119 



tioned side. What to call this bladder or vessel, I do not 

 yet determine : scrotum I must not, for that the testicles 

 (very pretty to a curious eye) are within the abdomen. 

 Whether in or nigh this vessel is one of the glandules 

 prostratse, and whether there are any vesiculse seminarise 

 within these, or any other besides these, I would farther 

 examine, I believe, but dare not assert, that the penis 

 on each side is annexed to these vessels ; some ramifica- 

 tions of the epididymis seem here, but not so plain as in 

 the abdomen. While I was searching for anything that 

 might be annexed to the foramina, which by Gesner are 

 called foramina vulvae (and very cunningly by Steno 

 passed over in silence), though they are in all males as 

 well as females, I cut with the os pubis so much as hin- 

 dered the discovery whether both penises might meet or 

 not. I am satisfied that those foramina serve only to let 

 in water into the abdomen, as those behind the eyes let 

 it into the mouth shut, the ten trapdoors or floodgates 

 of the branchiae being shut at pleasure ; and this receiving 

 in so much water, may be (if it be lawful to conjecture) 

 by the weight of the water to make her more swift in 

 pursuing prey, if at all, downward. 



Cambridge, June 31, 1675. 



Another Letter of Mr. Dent's to Mr. Ray, without date. 



Sir," — I could not in my last, of the 1 5th instant, give 

 you any good account of the eggs of flair or thornback, 

 because they were very small then, and only in the vitel- 

 larium. Since that I have found a female flair with two 

 eggs in shells in the duplex ovarium, as Dr. Needham 

 observes in his ' Disquisitio Anatomica,' p. 202. The 

 one I dried whole and have it by me : I opened the other 

 and found the vitellum to be grown flat, swimming in the 

 albumen, and with moving the egg upwards or downwards 

 (I mean whilst whole) would easily glide through the 



