ANATOMY. 



ings antl convolutions, into a comparative- 

 ly small space. These convolutions of the 

 small intestine occupy the chief part of 

 the umbilical and hypogastiuc regions of 

 the abdomen. They are connected in 

 their situation by means of a broad folded 

 membrane, called the mesentery. This 

 production of the peritoneum is about six 

 inches broad at its commencement, but it 

 expands gradually, something 1 after the 

 manner of a fan, so that it becomes broad 

 enough, ultimately, to cover the whole 

 length of the small intestine. It serves to 

 keep the different convolutions of the ca- 

 nal in a certain relative position, and al- 

 lows, at the same time, a considerable 

 freedom of motion, without any danger of 

 intangling. In tracing the course of the 

 small intestine, we follow the duodenum 

 iron* the lesser extremity of the stomach, 

 in the right hypochondrium, making three 

 turns close on the backbone, and then 

 coming- out just over the left kidney. The 

 gentvai direction of the canal from this 

 point, independently of its various turn- 

 in !.'/; ah > windings, is towards the right 

 groin, where the ilium terminates by en- 

 tering ihe coecum. 



The small intestine possesses three 

 coats similar to those of the stomach, viz. 

 an external or peritoneal ; a middle or 

 muscular ; and an internal, or villous. tu- 

 nic. The latter forms a great many trans- 

 >erse, loose, and Moating processes, call- 

 ed valvulx conniventes ; by means of 

 which the extent of surface of the villous 

 coat is very much augmented. Numerous 

 glandular bodies are found in parts of the 

 canal, collected into small parcels, and 

 hence called glandular agminate. 



The food, which is reduced by the ac- 

 tion of the stomach into an homogeneous 

 mass, called chyme, enters the small in- 

 testine, where it undergoes a further 

 change, and becomes chyle. It is pro- 

 pelled along the canal by the muscular 

 coat of the intestine, and the villous tu- 

 nic absorbs from it the nutritious parti- 

 cles. It pusses along every turn and wind- 

 ing of this long canal, continually subject- 

 ed to the action of the absorbing vessels. 

 The residue of the alimentary matter is 

 sent into the large intestine, from which 

 it is expelled in the form offices. 



The large intestine is a canal of about 

 two or three inches in diameter, and seven 

 feet in length. It is divided into the cce- 

 cum, colon, and rectum. The coecum is a 

 bag situated in the right groin, and receiv- 

 ing the termination of the ilium. The 

 latter interstice enters in such a manner, 

 jhat the passage of the aliment is allowed 



YWL. !. 



from it into the ctecum, but prevented 

 from returning. The part which effects 

 this is called the valvula coli. A small 

 process, about equal in size to an earth- 

 worm, is connected to the coecum. It is 

 culled appendix cceci vermiibrmis, and its 

 use is unknown. 



From the right groin the intestine 

 ascends on the right side of the abdomen 

 over the kidney, under the name of co- 

 lon : it turns completely over the abdomen 

 at the upper part, and descends along the 

 lef- side to the left groin ; here it makes 

 a large turn over the brim of the pelvis, 

 and enters that cavity, where it takes the 

 name of rectum, which terminates at the 

 anus. We distinguish in the colon the right 

 or ascending portion ; the middle or trans- 

 verse arch ; the. left or descending ; and 

 the sigmoid flexure. The right and left 

 portions of this gut are closely bound 

 down in their situations by two portions 

 of peritoneum, called ligamenti coli. The 

 transverse arch h:is a broad process con- 

 nected to it, by which it is loosely attach- 

 ed : this is called the mesocolon. 



Tiie large intestines have a peritonea], 

 a muscular, and a villous coat ; but they 

 have no valvulx conniventes. The longi- 

 tudinal muscular fibres are collected into 

 three bands, whi< :> being shorter than the 

 rest of the intestine, occasion the rUier 

 coatsto be gathered up in in folds bei w t ^n 

 them, and thereby give the intestine a 

 sacculated appearance. 



The residue of the alimentary matter, 

 which the large intestine receives from 

 the small, is converted in the former ca- 

 nal into a substance of peculiar odour, 

 colour, and consistence, called faeces ; in 

 which form it is expelled from the body. 



Parts subservient to the functions of the ali- 

 mentary canal, and contained in the cavit'it 

 of the abdomen. 



The liver is the larg-est glandular msrss 

 in the body, and is placed towards the 

 right side of the epigastric region. Ifr, 

 thickest portion fills the right hypochon- 

 drium; a thinner part of the gland extends 

 across the middle of the epigastric region 

 to the left hypochondrium. Its size is 

 greater in proportion as the animal is 

 younger. In the adult it is contained 

 within the cartilages of the ribs ; but in 

 the foetus it extends to the navel, and fills 

 half the belly. Its upper surface is con- 

 vex, and in close contact with the concave 

 under surface of the diaphragm. Its under, 

 or concave surface rests chieHy on the 

 stomach. It is divided into a ri^ht and 

 left lobe, .and lobulus spigelu. It has a 



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