072 PHILOSOPHICAL TRANSACTIONS. [aNNO 1683. 



The vesiculae seminales were 14- inch long; in some places -j-, in others half 

 an inch broad. Though called vesiculae, yet here they appeared more glandu- 

 lous ; nor was their cavity very large. The common orifices to them and the 

 vasa deferentia made a rising in the inside of the urethra, which de Graaf calls 

 caput gallinaginis ; in men and other animals there is a better resemblance and 

 show for the name. In those too, at this place, is seated that glandulous body 

 called the prostatae. But the vesiculae here being so glandulous, possibly they 

 may perform their office ; unless we should ascribe their use to those two 

 glands, which lay on each side the urethra, and emptied themselves with two 

 orifices, near the root of the penis. These glands were cylindrical, of a whitish 

 yellow colour, an inch and half long, and 4^ of an inch in diameter. Theit 

 substance was close, like that of the testes, and no perceptible cavity within ; 

 and they lay along the outside of the urethra, reaching from the musculi 

 erectores penis to the glandulous vesiculae before described. The penis in our 

 taja(5u was a long slender body, composed of several muscles, whereof two 

 were very long. The vesica urinaria, or bladder of urine, was rounder than in 

 8ome other animals ; where usually it is more oblong. The ureters were in- 

 serted at the neck of the bladder. 



In the thorax, the structure of the aorta was uncommon. For as it descends 

 along the spine in all other animals, its trunk almost of an equal breadth, only 

 a little tapering downwards; here, between the heart and its branchings 

 into the iliac arteries, we found three large aneurisms or tumours. The largest 

 was that nearest the heart, which, after a small contraction, emptied itself into 

 the second ; and this, though less than the first, was yet much larger than the 

 third, which was near the division of the aorta into the rami iliaci. Two of 

 these swellings I opened ; and found within several unequal cells or hollows ; 

 and the membranes here were altogether as thick as where the artery was not 

 extended. 



These extensions of an artery are called aneurismata; as those of a vein, va- 

 rices ; and are reputed to happen, when the inward coat of the artery is burst, 

 and so gives way for the extension of the outward ; and commonly they have 

 been occasioned by pricking an artery, instead of a vein. But what should be 

 the cause of it, in our subject, is most difficult to assign. For, it being the 

 only one of the kind I have dissected; I know not how far it may be preterna- 

 tural, or to be met with again. If preternatural, it is the more remarkable 

 here, because this is the strongest and thickest artery in the whole body. If 

 natural, there is nothing I can at present better parallel it with, than those pro- 

 tuberant swellings in the aorta of silkworms, and other such insects, which 

 Malpighi takes for so many several hearts. Which must be allowed him, un- 



