The addition of a careful dissection of a flower greatly increases the value of the specimen.
He worked enthusiastically at dissection, though, the liberty of the Alexandrian schools no longer existing, he could dissect only animals, not the human body.
His knowledge of anatomy, physiology and pathology was necessarily defective, the respect in which the dead body was held by the Greeks precluding him from practising dissection; thus we find him writing of the tissues without distinguishing between the various textures of the body, confusing arteries, veins and nerves, and speaking vaguely of the muscles as " flesh."
The second step is the conversion of one figure into another by a process of dissection, followed by rearrangement of parts; the figure as rearranged being one whose area or volume can be calculated by methods already established.
Extensive and deep-seated crumpling was necessarily accompanied by vertical uplift throughout the zone affected, but once at least since their birth the mountains have been worn down to a lowland, and the mountains of to-day are the combined product of subsequent uplift of a different sort, and dissection by erosion.
The difficulty should, wherever possible, be removed by making the process of dissection and rearrangement complete.
- The following are expressions for the areas of some simple figures; the expressions in (i) and (ii) are obtained arithmetically, while those in (iii) - (v) involve dissection and rearrangement.
He had made special inquiries of the authorities of the Sydney, Melbourne, Brisbane and Hobart museums, and published questions in the newspapers, but no evidence has reached him that the eggs of Ornithorhyncus have ever been obtained except by the dissection of the mother.
The very large assemblage of forms coming under this order comprises the most highly developed predaceous sea-snails, numerous vegetarian species, a considerable number of freshwater and some terrestrial forms. The partial dissection of a male specimen of the common periwinkle, Littorina littoralis, drawn in fig.
Between 1666 and 1669 Perrault edited at Paris eight accounts of the dissection by du Verney of as many species of birds, which, translated into English, were published by the Royal Society in 1702, under the title of The Natural History of Animals.
It is convenient to place in a small envelope gummed to an upper corner of the sheet any flowers, seeds or leaves needed for dissection or microscopical examination, especially where from the fixation of the specimen it is impossible to examine the leaves for oilreceptacles and where seed is apt to escape from ripe capsules and be lost.
The cerebral mass is in Limulus more easily separated by dissection as a median lobe distinct from the laterally placed ganglia of the cheliceral somite than is the case in Scorpio, but the relations are practically the same in the two forms. Formerly it was supposed that in Limulus both the chelicerae and the next following pair of appendages were prosthomerous, as in Crustacea, but the dissections of Alphonse Milne-Edwards (6) demonstrated VI FIG.
1 The anatomical error in reference to the auricles of Reptiles and Batrachians on the part of Linnaeus is extremely interesting, since it shows to what an extent the most patent facts may escape the observation of even the greatest observers, and what an amount of repeated dissection and unprejudiced attention has been necessary before the structure of the commonest animals has become known.
Owen not only occupied himself with the dissection of rare animals, such as the Pearly Nautilus, Lingula, Limulus, Protopterus, Apteryx, &c., and with the description and reconstruction of extinct reptiles, birds and mammals - following the Cuvierian tradition - but gave precision and currency to the morphological doctrines which had taken their rise in the beginning of the century by the introduction of two terms, " homology " and " analogy," which were defined so as to express two different kinds of agreement in animal structures, which, owing to the want of such " counters of thought," had been hitherto continually confused.
The dissection of the human body, of which some doubtful traces or hints only are found in Greek times, was assiduously carried out, being favoured or even suggested perhaps by the Egyptian custom of disembowelling and embalming the bodies of the dead.
If this cannot be done, the main artery of the limb must be exposed by dissection at the most accessible point between the wound and the heart, and there ligatured.
This condition can be ascertained without dissection, when the mouth is opened widely.
Servetus succeeded Vesalius as assistant to Gunther, who extols his general culture, and notes his skill in dissection, and ranks him vix ulli secundus in knowledge of Galen.
Here, partly because of elevation, and partly because of the resistant nature of the Catskill sandstones, dissection has so sculptured the plateau as to carve it into a mountainous mass which is generally known as the Catskill mountains.
The height is greatest along the inner or north-western border of the belt, and here a sub-mountainous topography has been produced by normal dissection, chiefly in the Tertiary cycle; the valleys being narrow because the rocks are resistant.
But in general the dissection of the New England upland is as irregular as is the distribution of the surmounting monadnocks.
Again, in Kentucky and Tennessee, there is a double alternation of sandstone and limestone in the plateau-making strata; and as the skyline of the plateau bevels across these formations, there are west-facing escarpments, made ragged by mature dissection, as one passes from the topographically strong sandstone to the topographically weak limestone.
The submature or mature dissection of the plateau by its branching insequent streams results in giving it an excess of sloping surface, usually too steep for farming, and hence left for tree growth.
As in the Atlantic coastal plain, it is only the lower, seaward part of this region that deserves the name of plain, for there alone is the surface unbroken by hills or valleys; the inner part, initially a plain by reason of its essentially horizontal (gently seaward-sloping) structure, has been converted by mature dissection into an elaborate complex of hills and valleys, usually of increasing altitude and relief as one passes inland.
Mt Taylor in western New Mexico is of similar age, but here dissection seems to have advanced farther, probably because of the weaker nature of the underlying rocks, with the result of removing the smaller cones and exposing many lava conduits or pipes in the form of volcanic necks or buttes.
In the north, where dislocations have invaded the field of the horizontal Columbian lavas, as in south-eastern Oregon and north-eastern California, the blocks are monoclinal in structure as well as in attitude; here the amount of dissection is relatively moderate, for some of the fault faces are described as ravined but not yet deeply dissected; hence these dislocations appear to be of recent date.
In the new altitude of the mountain mass, its steep eastern face has been deeply carved with short canyons; and on the western slope an excellent beginning of dissection has been made in the erosion of many narrow valleys, whose greatest depth lies between their headwaters which still flow on the highland surface, and their mouths at the low western base of the range.
The definite erection of the Mollusca into the position of one of the great primary groups of the animal kingdom is due to George Cuvier (1788-1800), who largely occupied himself with the dissection of representatives of this type.
Deep, but west of the Allegheny river, where harder rocks have resisted such deep dissection and glacial drift has filled depressions or smoothed rough surfaces, the uplands are broader and the valleys wider and shallower.
- Dissection of the renal organs (nephridia) of Chiton siculus.
The sloping surface is gently rolling, and has resulted from the uplift and dissection of a nearly level plain of erosion developed on folded, crystalline rocks.
The dissection of the first book, for instance, turns partly on a chronological inaccuracy which might well escape the poet as well as his hearers.
(2) Dissection of Amphioxus.
The most unpleasant portions of Jefferson's Anas are those in which, with an air of psychological dissection, he details the storms of passion into which the president was driven by the newspaper attacks upon him.
He was much interested, too, in universal algebra, non-Euclidean geometry and elliptic functions, his papers "Preliminary Sketch of Bi-quaternions" (1873) and "On the Canonical Form and Dissection of a Riemann's Surface" (1877) ranking as classics.
The dissection of the great east and west anticline in the south-east of England has resulted in a remarkable piece of country, occupying the east of Hampshire and practically the whole of Sussex, Surrey and Kent, in which each geological stratum produces its own type of scenery, and exercises its own specific influence on every natural distribution.
In later years Proudhon himself confessed that "the great part of his publications formed only a work of dissection and ventilation, so to speak, by means of which he slowly makes his way towards a superior conception of political and economic laws."
The dissection is viewed from the ventral side, and the lips (L) have been cut through in the middle line behind and pulled outwards so as to expose the jaws (j), which have been turned outwards, and the tongue (T) bearing a median row of chitinous teeth, which branches behind into two.
The disturbances among the underlying rocks of Ohio have been slight, and originally the surface was a plain only slightly undulating; stream dissection changed the region to one of numberless hills and valleys; glacial drift then filled up the valleys over large broken areas, forming the remarkably level till plains of northwestern Ohio; but at the same time other areas were broken by the uneven distribution of the drift, and south-eastern Ohio, which was unglaciated, retains its rugged hilly character, gradually merging with the typical plateau country farther S.E.
Garrod communicated to the Zoological Society the results of his dissection of examples of 82 species of parrots, which had lived in its gardens, and these results were published in its Proceedings for that year (pp. 586-598, pls.
Farther S., is the Cumberland Plateau, or Tennessee Valley region, broken into broad table-lands by the dissection of rivers.