SOLIPEDA. 



713 



of solid matter being very small, and its pro- 

 portion of water great, and the softness con- 

 siderable, 



Fibrous tissue resembles cartilage in its 

 alterations of cohesion, and both are apt to 

 become indurated by a deposit of osseous 

 matter. 



Softening of the muscular structures may oc- 

 cur, as a sequel of inflammation in the cellular 

 tissue which surrounds and binds together 

 the ultimate fibres ; or as a result of long con- 

 tinued inaction, produced by loss of nervous 

 influence, as in paralysis, or by long standing 

 disease. Softened muscles are pale, flabby, 

 and contain much fat ; are incapable of long or 

 severe action, and are deficient in irritability. 



Softening of the muscles of organic life, 

 generally depends upon an inflammatory con- 

 dition of their neighbouring submucous or 

 subserous cellular tissue. 



Softening of cellular tissue is very common. 

 It has already been noticed as occurring from 

 effusion of serum, pus, and blood. These ren- 

 der it more palpable and more liable to be 

 torn, and its simple lacerability is frequently 

 set down to softening : it is difficult, however, 

 to draw the line. A great consequence of 

 softening of the cellular tissue, is softening of 

 the subjacent and neighbouring tissues; we 

 have noticed this to a considerable extent in 

 softening of the sub-pleural tissue, and also of 

 the submucous and subperitoneal tissue of the 

 alimentary canal. 



There is hardly any part of the body in 

 which cellular tissue is not to be found ; and 

 consequently nearly all the tissues may be 

 influenced by its softened state. The effusion 

 of fluids into the areolae of the cellular tissue, 

 may follow inflammatory action or may be 

 produced from a malignant or typhoid state of 

 system, and from post mortem causes. 



The colour of the softened membrane de- 

 pends upon the nature of the effused fluid. 



Induration of cellular tissue is generally caused 

 by the effusion, and subsequent contraction 

 and hardening of coagulable lymph ; or the 

 simple effusion may produce hardening, as in 

 the immediate vicinity of old ulcers. How- 

 ever, it is notorious that even in this case con- 

 traction and consolidation occur at a little 

 distance from the seat of irritation ; in certain 

 skin diseases, and in the cicatrices following 

 burns, great injury may be effected by the 

 contracting power of the effused lymph. 



But it is behind mucous and serous, or sero- 

 fibrous membranes, that induration from in- 

 flammatory action principally occurs, and 

 leads to effects, most noxious to the general 

 economy ; strictures of the gullet, pylorus, in- 

 testines, and urethra, depend upon the sub- 

 mucous or subserous effusion and consoli- 

 dation of lymph. 



A hardened state of the mammary gland 

 depends upon the same cause. Dense, crisp- 

 cutting consolidations of cellular tissue, are 

 frequently mistaken for scirrhus, and, indeed, 

 are frequently the seat of morbid growths. 



Induration of the cellular tissue may de- 

 fend upon a perverted state of the general 



nutrition ; in syphilis, for example, there is 

 frequently subperiosteal effusion of lymph, 

 which has a tendency to ossify. It is also 

 very frequently brought about, and becomes 

 cartilaginous in hardness, by long continued 

 local irritation. We notice the indurated 

 state of the tissue around scrofulous glands, 

 and its condensed form around miliary tu- 

 bercles. The disease, which has been termed 

 hardening of the cellular tissue, occurs in 

 infants. The subjects of this disease are, for 

 the most part, feeble, sometimes imperfectly 

 developed, and generally born before the full 

 period. It is a disease seen, for the most 

 part, in hospitals, and is found where filth, 

 bad ventilation, and worse food abound ; con- 

 sisting, in a wax-like hardness of the sub- 

 cutaneous cellular tissue, and is produced by 

 the effusion of a sero-albuminous fluid into its 

 meshes. This effusion produces swelling of 

 the affected parts, as well as hardening ; and 

 occurs, first of all, in the inferior extremities, 

 passes from the feet upwards, and subse- 

 quently attacks the hands, arms, and then the 

 trunk itself. 



The hardened limbs are dry, cold, and may 

 or may not pit on pressure ; their colour is 

 either unchanged, or has a dull yellow or a 

 lived hue. Symptoms of obstructed respira- 

 tion supervene before death. 



When a section of an affected limb is made, 

 and the subcutaneous cellular tissue is well 

 exposed, we find its cellular appearance much 

 increased, from the interstices being filled 

 with a fluid, which is either limpid, or more 

 concrete, and of a citron colour, or tinged 

 with blood. The quantity of this fluid de- 

 termines the degree and amount of induration ; 

 and occasionally the fatty structure beneath 

 the skin is hardened from the compressing in- 

 fluence of the effusion. 



It is very doubtful if the effused fluid be- 

 comes wholly concrete. Chevreul says, that 

 the serum of the blood, in infants affected with 

 hardening of the subcutaneous cellular tissue, 

 contains a large quantity of a spontaneously 

 coagulable matter, analogous to that which is 

 effused into the affected tissue. Great and 

 general venous congestion is always found in 

 these cases, and would seem to depend on in- 

 sufficient vital energy, produced by the de- 

 pressing influences of damp, bad nourishment, 

 and cold. 



For some particulars respecting the Soften- 

 ing and Induration of " Growths," see article 

 on ADVENTITIOUS PRODUCTS. 



(P. Martin Duncan.) 



SOLIPEDA. Syn. Solidungula, Pachy- 

 dermes Solipedes. An important group of 

 herbivorous quadrupeds, regarded by Cuvier 

 as constituting a third family of his order 

 Pachydermata, and defined as " animaux a 

 sabots non ruminans," or non-ruminant, un- 

 gulate quadrupeds. They form, however, 

 a race of animals that presents many remark- 

 able peculiarities of structure, and, from their 

 great importance to mankind, demand, in a 

 work like the present, a somewhat minute 



