334 DR. E. KLEIN. 



The above-iiatned varicosities and the different condition 

 of the sheath and central bundle in the varicose and inter- 

 varicous portions bear a very strong support to this view ; for 

 the varicosities are in all probability portions of the muscle- 

 fibre in a state of contraction, and hence the narrowness 

 of the transverse rinj^s, the thickness of the sheath, and the 

 breadth of the central bundle of fibrils. Another point which 

 can be, 1 think, only interpreted in the sense of this theory, 

 is the fact that in the thicker muscle-fibres we find the 

 sheath thicker and the annular markings much closer and 

 more numerous than in the thinner examples. 



As a last fact of some interest may be mentioned the ter- 

 mination of these muscle- fibres. I have noticed in a few 

 instances that the extreme end does not terminate in a free 

 point, but is either at or near this in connection with the 

 Jine processes of a connective-tissue corpuscle. 



IV. TJie connective-tissue corpuscles. 



a. The migratory cells are in some parts more numerous 

 than in others, but they are to be met with in almost all 

 portions of the mesentery. IMost of them are possessed of 

 coarse granules and are of various shapes — elongated, con- 

 stricted, irregular, and possessed of knob-like prominences. 

 Their nucleus is generally single, oval and large, or in some 

 instances constricted, but in all cases it shows a beautiful 

 intranuclear network (see figs. wiO and 21). In some of these 

 cells the nucleus as a whole is more deeply stained (in car- 

 mine as well as in hsematoxylin) than in others, and I con- 

 clude that the ground-substance of the nucleus is in these 

 instances of a diff"erent nature, the whole cell being younger. 

 A minority of migratory cells i)ossess a pale, slightly and 

 indistinctly fibrillar substance surrounding the relatively 

 large nucleus, and a few knoblike or filamentous 

 processes. The nucleus of these cells shows the net- 

 work of fibrils with equal distinctness. Also in the nuclei 

 of many of these cells we find the ground-substance of the 

 nucleus staining a deep tint. 



h. Tile connective-tissue corjmscles proper or fixed cells 

 present themselves in great delicacy and beauty, both in speci- 

 mens stained in picrocarmine as well as hicniatoxylin. What 

 attracts our attention in the first instance is the remarkable 

 distinction between a hyaline, slightly but distinctly tinted 

 ground-plate and the fibrillar substance or intracellular net- 

 ivorh of fibrils, which forms a collection round the nucleus 

 and is prolonged beyond {hv (/round- ])I(ilc in numerous richly 

 branched j)ro(.cs-<'s, \\ Inch in some instances foiui a con- 



