194 



and lympha 

 dafts. 



Kervcsofvolun 

 tary mufcles. 



Origin of the 

 serves of voli- 

 tion. 



Mufcles for in- 

 voluntary 



OI* MUSCULAR MaTlON, 



The lymphaeduds are not fo numerous as the blood vefi«ls» 

 and certainly do not extend to every mufcular fibre: they 

 appear to receive their contained fluids from the interfticial 

 fpaces formed by the reticular or cellular membrane, and 

 not from the projecting open ends of tubes, as is generally 

 reprefented. This mode of receiving fluids out of a celJular 

 firudure, and conveying them into cylindrical vefl^els, is ex- 

 emplified in the corpora cavernofa, and corpus fpongiofunl 

 penis, where arterial blood is poured into cellular or reticular 

 cavities, and from thence it pafles into common veins by the 

 gradual coardation of the cellular canals. 



In the common green turtle, the ladteal velPels univerfally 

 arife from the loofe cellular membrane, fituated between the 

 internal fpongy coat of the inteftines and the mufcular coat. 

 The cellular ilruclure may be filled from the lacleals, or tlie 

 ladeals from the cellular cavities. When injeding the-fmaller 

 branches of the Iymph2cdu6ls retrograde in an osdematous 

 human leg, I faw, very diftindly, three orifices of thefe veiTels 

 terminating in ll>e angles of the cells, into which the quick- 

 ftlver trickled. The preparation is preferved, and a drawing of 

 the appearance made at the time. It wasalfo proved, by mai>y 

 experiments, that neither the lympha?du6ls, nor the veins, 

 have any valves in their minute branches. 



The nerves of voluntary mufcles feparate from the fame 

 bundles of fibrils with the nerves which are diftributed in th« 

 fkin, and other parts, for fenfation; but a greater proportion 

 of nerve is appropriated to the voluntary mufcles, than to any 

 other fubilances, the organs of the fenfes excepted. 



The nerves of volition all arife from the parts formed by 

 the junction of the two great mafl!es of the brain, called the 

 Cerebrum and Cerebellum, and from the extenfion of that 

 fubfiance throughout the canal of the vertebrae. Another 

 clafs of mufcles, which are not fubjedl to tlie will, are fupplied 

 by peculiar nerves; they are much fmaller, in proportion to 

 the bulk of the parts on which they are diftributed, than thofe 

 of the voluntary mufcles; they contain lefs of the white 

 opaque medullary fubftance than the other nerves, and unite 

 their fibrils, forming numerous anaftomofes with all the other 

 nerves of the body, excepting thofe appropriated to the organs 

 ©f the fenfes. There are enlargements at feveral of thefe 



jiindions^ 



