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ORIGINAL ARTICLES. 



Uterine Arteries, &c. 



In the uteri of children, of which I have several well injected 

 preparations, the right and left arteries appear to he as independent 

 as those of the heart. An injection of the arteries of one side is always 

 followed by the perfect filling of the vessels of that side, and the absence 

 of injection in the other. However, in the vagina, and more espe- 

 cially in the bladder, there are large anastomoses between the right 

 and left arteries of these organs, a circumstance which is of some im- 

 portance in the development of certain pathological changes. When, in 

 man, there are two, three, four, or even (as sometimes) five renal arte- 

 ries, you may inject one, and yet none of the others will be filled, every 

 one of these arteries having a distinct province of its own. It is the 

 same case in other Mammalia, when their kidneys have more than 

 one artery entering at different portions of their surface ; for instance, 

 when an injection of the horse's kidney is made, one can spare the 

 injected matter, by selecting any small artery which enters the ex- 

 ternal surface of the organ (not in the hilus). A minute injection 

 of a very limited portion of the cortex is thus obtained, and there 

 is no risk of wasting the injected material by filling other parts, not 

 required for the preparation. 



Menengea media. 



An isolated injection of the middle meningeal artery makes it 

 evident, that this artery is not only destined to be the nutritive artery 

 of the cranium, but also, that very numerous off-sets of the diploetic 

 branches pass out to the external surface of the calvarium and ramify 

 freely throughout the pericranium. When a well injected prepa- 

 ration of this artery is exposed to the action of weak hydrochloric 

 acid, the destruction of the earthy matter gives to the skull (after 

 being well dried and saturated with turpentine) such a degree of 

 transparency, that the perforating branches of the diploetic arteries 

 can be distinguished with the greatest facility. 



Arteria occipitalis. 



It happens very often, that the occipital artery seems to send a 

 branch through the mastoid foramen ; it is very commonly believed 

 that this branch appertains to the dura mater, and is an accessory 

 nutritive artery (Art. meningea externa accessoria). Now, when a 

 series of isolated injections of the occipital artery are made, it is 

 easy to show that, in many instances, the artery which passes into the 

 mastoid foramen does not pass through' it, and that it is, therefore, no 

 meningeal artery. The hammer and chisel, or the help of muriatic 



