116 



SPECIAL HISTOLOGY. 



O006 — 0*016'" in extreme cases, and resemble tesselated 

 epithelium- cells in form, except that they are more irregular. 

 Their membrane is delicate, and perfectly closed, and their 



- contents, in perfectly 

 normal livers, such as are 

 rarely met with in man, 

 but readily enough in 

 animals, are a granular, 

 yellowish, semifluid sub- 

 stance, which, as mi- 

 croscopic investigation 

 shows, probably contains 

 the essential element of 

 the bile. In this lies a 

 round vesicular nucleolated nucleus, of 0*003 — 0004"' ; and 

 in many cells there are two. Besides these, fat-drops and 

 pigment granules are frequently to be met with. The 

 former (fig. 220 e) occur in all the cells, when the liver 

 has undergone fatty degeneration, in such quantities that 

 they become very similar to certain forms of fat-cells; 

 and generally, as a few large or many small drops, entirely 

 fill the cell, so that the nucleus becomes invisible. Every 

 transition may be traced from these well-marked forms 

 to ordinary cells with a few minute drops or a single some- 

 what larger one ; and, in fact, these less fatty cells occur to a 

 certain extent in almost every body ordinarily subjected to 

 examination, so that if their absence in animals were not kept 

 in mind, their occurrence, at least to a small amount, might 

 be regarded as normal. The same may be said with respect 

 to the pigment molecules (fig. 220 b). When these are very 

 abundant they are certainly pathological; but when few, they 

 can only be regarded as a slight deviation from the normal 

 state. They are small, hardly exceeding O'OOl'", of a yellow, or 



Fig. 220. Hepatic cells of Man, x 400: «, more normal cells; b, with pigment; 

 c, with fat. 



fore draws the general conclusion, "that the secreting process hy no means requires 

 the formation of perfect cells in order to effect its peculiar changes ; these may cer- 

 tainly occur in hlastematous matter, if the nucleus only be present." • Philosoph. 

 Transactions,' 1849, p. 132.— Eds.] 



