The arteries of the prostate are usually derived from the vesical and hmmorrhoidal branches of the internal pudic, and from the tniddle hmmorrhoidal of the internal iliac, which, entering the gland on either side be neath its capsule, are distributed in the form of a network on the parietes of its tubes and follicles; the veins terminate in the vesical and hmmorrhoidal veins : its nerves, which are ex tremely small, are branches of the hypogastric plexus of the great sympathetic. The lym phatics consist of a superficial and deep set, and pass into the hypogastric ganglia. It happens occasionally that an artery of consi derable magnitude runs on either side of the prostate, from the internal iliac, and becomes the artery of the bulb of the urethra. This variety has been seen by Haller, Burns, and Barclay. I have witnessed a similar distri bution myself. Dr. Monro met with a case, in which an irregular vessel came from the internal iliac, passed along the lateral and in ferior surface of the bladder, pierced the ilio vesical fascia, ran along the lateral lobe of the prostate, and divided into three branches, one to the dorsurn, one to the crus penis, and another to the bulb. Other varieties in the course and distribution of the branches of the internal iliac, involving the prostate, have been occasionally met with, and I allude to them here as points of great interest in respect to the surgical anatomy of this body.
Liquor Prostaticus.— It is the office of the prostate to eliminate from the blood sent into its arteries a fluid called the liquor prostati cus. This has been examined microscopically; but in consequence of the difficulty in obtain ing it in any. large quantity, it has not hitherto been made the subject of chemical analysis. This fluid can be obtained after death by squeezing the gland, when it oozes through the orifices of the ducts around the veru rnontanum. It usually presents a turbid ap pearance, is of a thin milky aspect, and is somewhat unctuous to the feel. Haller found it in many cases coagulable by the addition of alcohol it contains, according to Krause, muddy flakes, or globules, filled with minute granules, varying from a. to .5,1-u of a line in diameter. Prevost and Dumas examined the liquor prostaticus of the dog, cat, hedgehog, and rabbit : they found it to contain globules like milk-globules. Cuvier remarked in the fluid of the hedgehog, numerous ovoid and spherical vesicles, others oblong and conical in shape : many of the vesicles presented a stellate aspect, and contained a central nu cleus. I have carefully examined, in many cases, the prostatic secretion of the human subject, in as fresh a state as I could possibly procure it. I have found it of a milky aspect, like a very weak mixture of milk with water. In sorne cases, I have seen it of a consistence more resembling cream. I consider the for mer state to represent the healthy fluid. Examined with the microscope, it vvas found to contain numerous molecules, epithelial cells, both pavement and cylindrical, in va rious stages of formation, and granular nuclei of about 0.0036 of a line in diameter. In by far the greater number of instances in which I have examined it, I have been rather surprised to find it give feeble but distinct signs of acidity when tested by litmus paper. I thought it not unlikely that the apparent acidity of the prostatic secretion was due to the cadaveric infiltration of urine through the tissue of the gland; but I adopted every pre caution, by carefully and repeatedly washing the surface of the bladder and urethra, to ob viate this source of fallacy, and the result was still the same. I have found a similar reaction in the prostatic secretion of an old man, in whom the gland was greatly hypertrophied ; and where the ducts and follicles were dis tended with an opaque creamy-looking fluid, such as is often seen after death. The ap
pearance of the liquor prostaticus may be, and probably is, very different after death to what it is during life. There is every reason to believe that it is secreted more clear and transparent, and it most likely owes much of its turbid appearance to the admixture of a large number of minute epithelial cells. I regret that I have nothing to offer as to its chemical constituents, as it is not possible to collect more than two or three drops at a time, a quantity too small to submit to che mical investigation. That the acidity of the liquor prostaticus is not incompatible with the existence of calculous concretions of the phosphatic species in the follicles of the gland, I have proved by repeated examination.
Utriculus prostaticus. Vesicula spermatica spuria. Vesica prostatica. Sinus pocularis. — At the anterior part of the most elevated por tion of the veru montanutn, we find an open ing in the mesial line one-third or half a line broad, leading backwards to a small bag re sembling a bottle in figure, of variable length and breadth : it is generally known by the name of the sinus pocularis, but has received also the designations here mentioned. In most eases in which I have examined it, it forms a canal, terminating in a blind extremity, and usually is not more than three or four lines long. I have found it an inch in length. The opening, which faces obliquely forwards, will just admit the point of a small catheter or bougie. Some surgical interest is attached to this structure, because it has been stated by writers on urethral diseases that an instru ment is liable to catch in it when an attempt is made to pass it into the bladder ; but I be lieve this very rarely happens, as the beak of the catheter is usually kept against the an terior surface of the urethra, when it is made to traverse the prostatic portion, and it is therefore carried well above this little pouch : it', however, such an accident should be sus pected to have occurred, a gentle withdrawal of the instrument and depression of the han dle are quite sufficient to clear the impedi ment referred to. But much physiological importance attaches to this sinus, for reasons which we shall presently see. Huschke de scribes it in the following manner : — It com mences by a narrow portion, resembling a neck, which forms about half its length, be hind which it swells out into a round mem branous vesicle or fundus; between these two portions there is often a constriction. It penetrates the posterior surfiice of' the pros tate gland, so that the middle lobe is situated in front of its fundus. Its parietes are thinner at the fundus than at the neck, and are usually about one-fourth of a line in thick ness. On either side a vas ejaculatorium is inclosed within its wall; so that, in point of fact, these ducts do not penetrate the glan dular substance of the prostate. Its walls are composed of two layers, an external, fibrous and strong ; an internal, of a mucous charac ter : the latter is covered by small mucous glands, arranged closely together, with open ings of about the twenty-fifth of a line in diameter. These glands resemble minute warts, each with a small opening on its apex. They cannot be confounded with. the orifices of the prostatic ducts, as these always open external to this pouch, around the veru mon tanum.. About its neck larger glandular open ings are perceptible. The nature of the se cretion of these glands is not known.