Quarterly Journal of Microscopical Science. Vol. XII

Quarterly Journal of Microscopical Science. Vol. XII

List price: US$20.76

Currently unavailable

Add to wishlist

AbeBooks may have this title (opens in new window).

Try AbeBooks

Description

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1872 edition. Excerpt: ...more fluid than the cortical substance. The grains it contains are rather voluminous, and very refracting; they are seen to change their places, and move under the influence of the contractions of the Gre-garinae. The middle parenchyma really constitutes a massive column, which completely fills the hollow cylinder, circumscribed by the cortical parenchyma. The nucleus of the cell, of which the form is usually ellipsoidal, occupies the entire breadth of the cylinder. If the body of a Gregarine still alive is cut transversely, either above or below the nucleus, the central fluid matter runs off in a columnar shape, without carrying away the nucleus with it; and since the cortical matter remains in its place, there develops inside the body a cavity, circumscribed on the outside by the cortical parenchyma, at the top by the nucleus, at the cut end by the exuding medullary column (fig. 6). When the medullary matter spreads, it dilates, the granules separate one from another, and continue diverging, each animated by very intense Brownian movements, each oscillating by itself. The cortical layer (Leidy's muscular layer) is composed of a slimy protoplasmic matter, much less fluid, much less granular, and, therefore, clearer than the medullary substance. The granules of the cortical parenchyma are not only less numerous, but much more slender and refracting, than those of the central column. Just as in Infusoria, there is to be found no strong line of demarcation between the two layers; there is an imperceptible passage from one to the other. Near the posterior extremity of the body these two substances are with difficulty distinguished. The surface of contact between the medullary parenchyma and the cortical parenchyma is not always a simple...show more

Product details

  • Paperback
  • 189 x 246 x 10mm | 327g
  • Rarebooksclub.com
  • United States
  • English
  • black & white illustrations
  • 1236670140
  • 9781236670144