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The ependymal cells bordering the median eminence to the third ventricle are characterised by many microvillus-like projections and bulbous cell processes of the luminal plasma membrane. The latter contain many vesicles 500-1,000 Å in diameter. Cilia with 9+2 fibrillar pattern are seen occasionally. Adhesive devices in the from of zonula adhaerens and zonula occludens are found in the apical part of the intercellular junction. Unmyelinated nerve fibres with a mean diameter of 1 μ and containing many electron dense granules of 830-1,330 Å are often seen between the ependymal cells. Two types of glial cells are found in the median eminence. One is characterised by a nucleus with dense blods of chromatin and dense cytoplasm, and it is associated chiefly with the nerve fibres in the region of the hypothalamo-hypophysial tract. The other type of glial cell is characterised by fine, uniformly distributed chromatin in the nucleus and a relatively pale cytoplasm and branched processes which terminate perivascularly in the base of the median eminence. Myelinated nerve fibres are seen only in the region of the hypothalamo-hypophysial tract. Only a part of them contain electron dense granules 1,330-2,330 Å in diameter. Three types of unmyelinated nerve fibres can be distinguished in the median eminence according to the size of the electron dense granules they contain: 1. Nerve fibres containing granules 1,330-2,330 Å in diameter. They are seen primarily in the hypothalamo-hypophysial tract, but also in the zona externa; 2. those containing granules with a mean diameter of 1,330 Å; and 3. those containing granules with a mean diameter of 1,000 Å. The last two types are both encountered in the hypothalamo-hypophysial tract, the zona externa and the perivascular region of the base of the median eminence. Under high magnification, the membrane of the granules show evidence of a trilaminar structure and the content of the granules with a low electron density appeares to consist of small microvesicles or globular components. Besides granules, these nerve fibres contain vesicles mostly 420 Å in diameter whose relative number increases towards the perivascular nerve endings. 53 per cent of the inclusions in the hypothalamo-hypophysial tract are granules and 47 per cent vesicles, while the corresponding percentages for the zona externa are 40 and 60 and for the perivascular nerve endings 20 and 80. The mean width of the pericapillary space is 1 μ, but it varies greatly. It containes many collagen fibrils and fibroblasts. The capillary endothelium is frequently fenestrated and contains many vesicles of various sizes. Two types of granules-containing cells are found in the pars tuberalis depending on the size of the electron dense granules: 1. cells containing granules with a mean diameter of 1,330 Å: and 2. cells containing granules with a mean diameter of 2,000 Å. In addition, there are occasional follicular cavities filled with amorphous material, microvilli and cilia of 9+2 fibrillar pattern. [ABSTRACT FROM AUTHOR]

The article discusses the issue of the English railway rate. The chief stages in English railway history may be described as follows in various stages. There was the period of doubt and suspicion as regards the national advantage and probable financial success of railways. This period was short. It really extended only from the promotion of the Liverpool and Manchester Railway in 1824 until about 1840. The great change in the attitude of public towards railways came about in the second period, when "the extreme of determined rejection or dilatory acquiescence" was exchanged for " the opposite extreme of unlimited concession." The Regulation of Railways Act of 1844 gave powers to the Treasury to revise the scale of "tolls, fares, and charges" of any railway company, when the dividends of the company exceeded 10 per cent. During the period from about 1840 until 1854 the railway network of England was practically created. It is true that this network was built on no definite plan, that it was financed on no very sound principles, that there was much chicanery in promotion, and much mismanagement afterwards.