GENERATION. 



ly in the torm of a (ingle cyll with fmooth fides, contained 

 in the cellular fubflance of the part. 



The vas, or JuSus deferens, is the tube which conveys the 

 femen from the epididymis to the urethra. Its fijrure is for 

 the mod part cylindrical, and it conhfts of a very Imall tube, 

 which v.'ill only admit a large bridle, with very thick fides. 

 Although its calibre is fo fmall, the diameter of the part on 

 a feftioii equals a line. Tlie fubflance of its fides is very 

 firm, and cuts like cartilage ; hence we Can dilHnguilh it by 

 the feel from the other component parts of the" cord, by 

 Aiding them between the finger and thumb in the living fub- 

 jeCl. The internal furface of the tube is fmooth. Nothing 

 of a mufcular ftruclure can be difcerned in its compofition. 



It arifes from the pofterior and inferior part of the epidi- 

 dymis, afcends behind and a little on the inhde of that organ, 

 and then continues its courfe along th: fpermatic cord be- 

 hind the velfels to the ring. Compreffion of this part occa- 

 fions the fame kind of pain as is experienced when the tefces 

 are injured ; and the very acute fuSering obferved on tying 

 the cord in caftration, has been explained by the circum- 

 flance of this tube being included in the ligature. Pef^iaps 

 tliis explanation may be doubted, as the nerves of the telles 

 are alfo amo-.ig the comprefTed parts ; hov/ever, the vas de- 

 ferens is eafily omitted, as its hard feel enables us to feparate 

 the veiTels which lie in front, and are connedled to it by a 

 loofe cellular fubftance. It pafies through the abdominal 

 cannl, holding the fame relative fituaticn to the fpermatic 

 veflels. It feparates from them behind the opening, and 

 then bends downwards and backwards along the furfacc of 

 the pfoas mufcle, and of the iliac veflels, to enter the pel- 

 vis. Here it becomes attached to the pofterior and lateral 

 part of the bladder, and defcends obliquely from without in- 

 wards, juil in the iituation where the peritoneum is refleft- 

 ed to the bladder from the fide of the pelvis, connected by 

 cellular fubltance on one fide to the bladder, and on the 

 other to the peritoneum, and fituatedin front of the reflum. 

 In this courfe it decuffates the umbilical artery, behind which 

 it pafles : it alfo crofles the ureter, being placed between 

 the lower extremity of that canal and the bladder. At 

 the lower and back part of the latter organ it turns for- 

 wards and invi-ards, fo as to approach tovv-ards the canal of 

 the oppofite fide, ftill connected to the furface of the blad- 

 der : in this direftion it continues along the under furface of 

 the organ, v\-ithin the veficula feminalis, and connefted below 

 by cellular fubltance to the rectum. In the neighbourhood 

 of the prollate, the two vafa deferentia are placed clofe to- 

 gether, and each unites juil at the furface of the gland, 

 with the anterior extremity of the veficula feminalis. The 

 canal, refalting from this junction, fometimes called the eja- 

 culatory duCt, penetrates the fubltance cf the proftate, from 

 below and behind, upwards and forwards, and opens in the 

 urethra at the fide of the veru montanum. 



The commencement of the vas deferens is a little convolu- 

 ted, and rather larger in its calibre : at the upper pai-t of the 

 teitisit becomeo ilraight iiT its courfe, and its area is dimi- 

 nilhed. Under the bladder it is con fiderably enlarged again, 

 where it lies along the inner edge of the veficula feminalis. 

 It has here fometimes a flightly ferpentine courfe, and pof- 

 feffes a flattened- form. Its cavity is proportionably aug- 

 mented, and, inftead of a cylindrical tube, prefents a reticula- 

 ted texture, like that of the veficulx feminales. Its furface 

 is irregular and tuberculated in confequence of this cellular 

 ftrufture. After receiving the tube of the veficula femina- 

 lis, it is again diminifhed remarkably in fize, and forms a 

 finall cylindrical canal. 



The vas deferens receires aiterial and T*nous ramifications 

 from the trunks, in the neighbourhood of which it paffeii 

 Nothing is known of its nerves. 



It is by no means common in animals for the vas defereni 

 to join the veficula feminalis in the manner already defcribed. 

 In all cafes where there are teiticles, that duct conveys th* 

 fecreted fluid into the urethra, there being no veficulae in 

 fome, while in others they terminate by feparate openings. 

 The communication between the two parts in man is a very 

 free one ; and, although the canal formed by their junftioii 

 proceeds in a itraight direction to its termination in the ure- 

 thra, yet quickfilver, or any other inje fted fluid, or air thrown 

 into the vas deferens, pafles into, and diitends the correfpond- 

 ing veficula before it gets into the urethra. The comprefliop. 

 of the common canal by the firm fubftance of the proftate, 

 the fmall fize of the tube and of its opening, and a particular 

 turn made by it, liave been afTigned to explain this fact. If 

 the injection is pufr.ed further, it will go i;ito the urethra. 

 Fluids thrown into the veficula alfo diftend the vas deferens, 

 but are more readily admitted into the urethra, as the ca- 

 pacity of that vefl'el is not confiderable. 



The -vefuule fminaks are tvvo foft bodies, refembling, 

 when undifl;urbed by diffedtion, membranous tubes with 

 blind extremities, convoluted, and therefore marked with 

 rifings and grooves on their furface. They are' fituated un- 

 der the inferior flattened furface of the bladder, and upon 

 the upper furface of the redtum, being connected to both 

 thefe organs by loofe cellular adliefions. They are pyri- 

 form, with the apex placed forwards, and the bafis back- 

 wards, and convergent from behind forwards. Their ante- 

 rior extremities, joined, as we have already mentioned, to 

 the vafa deferentia, lie on the upper and back part of tlie 

 proftate, and would be in contact with each other, were 

 they not feparated, by the tabes juft alluded to. From 

 this point they grow gradually broader, and are divergent, 

 terminating behind in rounded ends, which are the moft dii- 

 tant from each other. The fuperior furface, in contadt witli 

 the bladder, is rather flattened : the inferior, lying upon the 

 redtum, is flightly convex. The vas deferens runs in con- 

 tadt with the inner margin, and the outward edge is turned 

 towards the fide of the bladder. Tlie pofterior broad and 

 rounded ends are partly in contadt with tiie peritoneum, 

 and he at the fides of the pouch, formed where that mem- 

 brane is refledted from the bladder to the rectum. Nume- 

 rous arterial and venous ramifications, particularly the latter, 

 and a confiderable quantity of cellular fubltance, furround 

 thefe organs in all diredtions, and connedt them to the 

 neighboi'j-ing parts. In fome individuals the pyriiorm 

 fhape is not well marked ; but the anterior and lower end 

 is always fmall. Tlie flattened appearance of its furfaces 

 is altered by injection : the whole organ then appears thick- 

 er, and the tubercular rifings of the fiu-face are more dif- 

 tmdt. 



A. very different appearance is produced when th.efe bo- 

 dies are unravelled by the anatomift. Each veficula is then 

 found to confift of a fiiigle tortuous tube, about the fize of a 

 writing quill, with a blind esiremity, and fevera! lateral ap- 

 pendices, which alfo end in cul-de-facs. Sometimes the lat- 

 ter are very few ; perhaps one or even none. In other in- 

 flances they may amount in num.ber to ten, or more. 

 Haller has feen fevcnteen larger, befides fmalkr ones. Some 

 of thefe are fimple blind appendices ; others, particularly 

 near the anterior end of the organ, again branch oat. 

 Sometimes the whole veficula is bifid almoft from its very 

 origin ; the varieties, indeed, are fo ntiir.erous, that 

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