MO CELLULAR TISSUE. 



strictus, t. cellularis stipatus), because it is mulated in those parts which are most move- 

 proper to the several constituent parts of the able. It is on this account that it abounds on 

 body, investing each of them, and penetrating the face, especially around the globe of the eye 

 into their internal structure. and about the cheeks, and also on the forepart 



Of the common cellular membrane. It is in of the neck and of the trunk in general. In the 

 this division that the connection to which we limbs it is met with in considerable quantity in 

 have just referred is most free. Thus in the the flexures of the joints, in the axilla, the 

 subcutaneous tissue placed between the skin elbow, the wrist, and in the palm of the hand ; 

 and the fasciae of the muscles, there is an uni- also in the groin, in the ham, in the front of the 

 versal and evident communication. Again, ankle, and in the sole of the foot. The super- 

 in the head, the cellular membrane of the exter- ficial muscles, which are very moveable, are 

 nal parts communicates with that of the internal separated from each other by thicker layers of 

 through all the natural apertures through the membrane than the deeper-seated and more 

 foramina of the base and other regions of the fixed. It may also be remarked that those 

 skull. From the face and cranium the con- important organs, which are most liable by their 

 nexion may readily be traced to the neck, structure or connexions to rupture or other 

 whence, after having pervaded all its parts, it effects of external violence, are carefully pro- 

 passes in one direction behind the sternum tected by being lodged in a large quantity of 

 and upper ribs to the thoracic cavity ; and in cellular substance. It is thus that we find the 

 another underneath the clavicle and scapula on pancreas and the kidneys enveloped in this 

 either side, to the arm-pit, which may be re- tissue in the abdomen ; the bladder and genital 

 garded as the common point of junction be- organs in the pelvis ; and the bloodvessels and 

 tween the cellular substance of the neck, the nerves in all parts of the body, 

 trunk, and upper extremity. Of the special cellular membrane. Each 



The cellular tissue of the thorax is continuous organ in the body is invested in a proper cover- 



with that of the abdomen through the openings ing of the cellular tissue, and also receives into 



of the diaphragm, and particularly beneath the its interior, processes which envelope and join 



sternum, around the aorta, the inferior vena together its component parts, 

 cava, and the oesophagus. In a similar manner The investing cellular membrane (t. cellu- 



the connexion may be followed from the abdo- laris strictus) is united by one of its surfaces, 



men to the pelvis; from the former of these the external, with the general cellular tissue, 



cavities under the crural arch to the inguinal and by the other or internal with that entering 



region, which constitutes the point of union into the organ. It presents many peculiarities 



between the trunk and the lower extremity ; as to the mode of its connexion ; the solid 



whilst from the pelvis the communication ex- parts, for instance, as the glands, muscles, and 



tends in one direction by the side of the rectum nerves, are entirely surrounded by cellular 



and urethra to the perineum, scrotum, and envelopes ; and a somewhat similar disposition 



penis ; and in another by the obturator fora- is observed around the bloodvessels, lympha- 



men and the ischiatic notch to the thigh. tics, and excretory tubes. On the contrary, 



In addition to these, which are the principal the skin, the mucous and serous membranes, 



connexions, the common cellular membrane is having one surface free or unattached, are only 



united in every direction with the special di- connected on one side with the cellular tissue, 



vision ; the details, however, of these commu- which is distinguished according to its situation, 



nications belong to the descriptive anatomy of by the terms subcutaneous, submucous, and 



the several regions, to the articles on which the subserous cellular tissue. The covering thus 



reader is referred. afforded to each individual organ serves in a 



The quantity of the interstitial tissue varies certain degree to insulate and separate it from 

 according to the age and temperament of the the surrounding structures, and in this manner 

 individual, and to the region of the body in it often tends to limit the progress of disease ; 

 which it is examined; but, independently of but as we have just seen that this covering is 

 any original differences which exist, it is well united both to the interstitial and to the pene- 

 known that the mode of living and habits of the trating cellular tissue, it would be equally con- 

 individual have a great influence in this respect : trary to reason and experience to expect that it 

 thus an habitual full diet, especially if con- should constitute, as some authorities have con- 

 joined with indolence, causes a great accumu- tended that it does, a species of atmosphere 

 lation of the cellular substance; whilst, on the around the various organs, confining their natu- 

 contrary, a spare or moderate diet and exercise ral actions and morbid phenomena, 

 will reduce it in a remarkable degree. These The penetrating cellular tissue (t. cellularis 

 differences depend, probably, more on the accu- stipatits) constitutes so essential a part of 

 mulation of serous fluid and on the repletion of organized structures, that there is no organ in 

 the bloodvessels, than on the actual increase which it may not be detected. It. exists in 

 of the proper filamentous tissue : we can in this the substance of bone, cartilage, and ligament, 

 manner, and in no other, understand how, by although it is distinguished in these structures 

 by what in England is called training, the bulk with difficulty, in consequence of their great 

 of the body may be so rapidly diminished. density ; it penetrates between the most minute 



The proportion of this tissue varies also in fibres of the muscles and nerves; between the 



the different regions of the body ; but as it is coats of the bloodvessels and lymphatics ; also 



in an especial manner subservient to the pro- between the layers composing the skin and 



duction of free motion, it is principally accu- rnuejus membranes; and lastly, it enters into 



