664 PHILOSOPHICAL TRANSACTIONS. [aNNO 1683. 



the following under the bull's horn, of the 5th magnitude. At present its 

 place is 19° ll' 3b" of H, and 4^ 43' 44^' south latitude. The other star B is 

 19° 17' of n, and in 4° 47' south latitude. And the star C, which is scarcely 

 to be seen with the naked eye, is now in 19° 9' of n, and 5° 2' south latitude. 



Historical Observations relating to Constantinople.* By the Rev. Tho. Smithy 

 D.D. and F.R.S. N° 152, p. 335. 



An Abstract of a Letter from Mr. Anthony Leuwenhoeck, concerning Generation 

 by an Animalcule of the Male Seed. Also on Animals in the Seed of a Frog ; 

 with some other Observables in the Parts of a Frog. And on Digestion and 

 the Motion of the Blood in a Fever. -f- N** 152, p. 347. 



Having been solicitous to examine the generation of frogs, J on account of 

 their young being like a worm, with a round thick body and a short tail ; I was 

 surprised to find that the male was not joined to the female in copulation, but 

 that he only sat upon her, and that he had no membrum masculum ; that at 

 the same time when the female cast her eggs or spawn, the male also dropped 

 his seed, which is to be spread under the eggs, in like manner as the seed of 

 fishes that want the membrum masculum is cast under the eggs of the female, 

 that the animalia in semine may conveniently impregnate the eggs. For I hold 

 it necessary that some one of the animals in semine should get into a certain 

 point § of the yolk of the egg, which point is only fit to receive it, and give it 

 the first nourishment, till such time as the egg comes to be sat on. But if no 

 one animal should find this point, then the egg is unfruitful ; and this may be 

 a reason why there are so many thousand more animals in semine masculo than 

 eggs in the female. 



In several of my observations I had not found the animals taken out of the 

 testicles and vasa deferentia of frogs to be alive. But on the 1st of April, when 

 frogs were ready to spawn, I took some of the males sitting upon the females, 



* So many accounts of this city have at different times been published by travellers and antiquaries 

 of our own and other nations, that it is deemed unnecessary to reprint this paper. Among the latest 

 and most accurate topographers of the capital of the Turkish dominions may be mentioned Mr. 

 Dallaway, formerly chaplain and physician of the British embassy to the Porte, and author of a De- 

 scription of Constantinople, ancient and modern, published in 1797- 



f The observations on digestion and on the motion of the blood in a fever are omitted, as being 

 irreconcilable with subsequent physiological discoveries. 



1 On this subject, the generation of frogs, three writers have distinguished themselves, viz. Swam- 

 merdam, Roesel, and Spallanzani. 



$ By this point or speck he means the cicatricula. — Orig. 



