Apparently correlated with this peculiar locomotion is the anatomical fact of the alteration of the myotomes on the two sides.
Are absent or vestigial in all other insects; and, in most genera, by the presence in the adult of abdominalappendagesused for locomotion, these latter varying in number from one to nine pairs.
The third body region or trunk may attain a great length, one or two feet, or even more, and is also muscular, but the truncal muscles are of subordinate importance in locomotion, serving principally to promote the peristaltic contractions of the body by which the food is carried through the gut.
Swimming is perhaps the commonest mode of locomotion, but numerous forms have taken to creeping or walking, and the robber-crab (Birgus latro) of the Indo-Pacific islands even climbs palm-trees.
Their organs of locomotion are the ribs, the number of which is very great, nearly corresponding to that of the vertebrae of the trunk.
Crime, with the many facilities offered for rapid locomotion to those who committed it, had ceased to be merely local, and the whole state rather than individual communities ought to be taxed; prison charges should be borne by the public exchequer and not by local rates.
The byssus is a collection of horny threads by which the sea mussel (like many other Lamellibranch or bivalve molluscs) fixes itself to stones, rocks or submerged wood, but is not a permanent means of attachment, since it can be discarded by the animal, which, after a certain amount of locomotion, again fixes itself by new secretion of byssus from the foot.
Moreover, the stationary habit of plants, and the almost total absence of locomotion, makes it impossible for them to seek their food.
Configuration of the palate, precoracoid, pelvis, intestinal convolutions, copulatory organ, &c. Loss of the keel is co-ordinated with the power of using the forelimbs for locomotion; although a " Ratite " character, it is not sufficient to turn a Notornis, Cnemiornis or Stringops, not even a Phororhacos into a member of the Ratitae.
It is now understood that they are Euthyneurous Gastropods adapted to natatory locomotion and pelagic life.
Following the metasoma in Limulus, we have as in Scorpio the post-anal spine - in this case not a sting, but a powerful and important organ of locomotion, serving to turn the animal over when it has fallen upon its back.
Beginning with a chapter on the means of locomotion in the 10th century, it went on to discuss war, the conflict of languages, faith, morals, the elimination of the unfit, and other general topics, with remarkable acuteness and constructive ability.
And III., capable of either locomotion or fixation at will, were either differentiated into alternating generations of fixed sterile nutritive hydroids (scyphistomoids) and locomotor sexual medusoids, or abandoned the power of fixation in hypogenetic cases.
In a few Ostracoda, by a rare exception, the masticatory process is reduced or suppressed, and the palp alone remains, forming a pediform appendage used in locomotion as well as in the prehension of food.
The foot arises as a prominence on the ventral surface and grows forward, and at the end of five or six days the velum atrophies and the foot becomes the organ of locomotion; the animal then ceases to swim and sinks to the bottom.
Its engine represented a third of a horse power, and the weight of the whole (engine, boiler, water, fuel, superimposed aeroplanes and ' " On Aerial Locomotion," Aeronautical Society's Report for 186.7.
Such an animal, if it ever existed, probably lived near the surface of the sea, and even here it may have changed its medusoid mode of locomotion for one in the direction of its mouth.
Electricity had even a greater effect on communication than steam oii locomotion; and electricity, as a practical invention, had its origin in the reign.
Prior to the introduction of carriages horseback was the means of locomotion, and Queen Elizabeth rode in state to St Paul's on a pillion; but even after carriages were used, horseback was held to be more dignified, for James I.
Birds being of all animals most particularly adapted for extended and rapid locomotion, it became necessary for him to eliminate from his consideration those groups, be they small or large, which are of more or less universal occurrence, and to ground his results on what was at that time commonly known as the order Insessores or Passeres, comprehending the orders now differentiated as Passeriformes, Coraciiformes and Cuculiformes, in other words the mass of arboreal birds.
Balfour put forward the view that the polyp was the more primitive type, and that the medusa is a special modification of the polyp for reproductive purposes, the result of division of labour in a polypcolony, whereby special reproductive persons become detached and acquire organs of locomotion for spreading the species.
The proboscis is not the only organ of locomotion, being assisted by the succeeding segment of the body, the buccal segment or collar.
- 1860), while with the improvement of the means of locomotion came the renewal of the old faith and the establishment of new methods in the use of mineral springs.
One of the most serious administrative problems met with in London is that of locomotion, especially as regards the regulation of traffic in the principal thoroughfares and at the busiest crossings.
Steam locomotion received much attention at his hands, and he sat on the railway commissions of 1836, 1839, 1842, 1845.
Swimming is effected chiefly by the action of the broad forepaws, the hind feet and tail taking little share in locomotion in the water.
The trochus forms the powerful currents for locomotion, and for the supply of food material, while the cingulum produces a local current round the upper rim of the corona to bring the food particles direct to the mouth, which is displaced through a postero-ventral gap in the trochus to lie behind the disk, just as occurs in the more specialized Ciliata.
Most remarkable is its resemblance to the adult form of the Wheel animalcules, or Rotifera, which retain the prae-oral ciliated band as their chief organ of locomotion and prehension throughout life.
An organ.ism the conditions of whose life render locomotion impossible great elaboration would seem superfluous.
The instincts of nest-building, incubation and the rearing of young, though they occur later in life than those concerned in locomotion and the obtaining of food, are none the less founded on a hereditary basis, and in some respects are less rather than more liable to modification by the experience gained by the carrying out of hereditarily definite modes of procedure.
In the so-called Selenariidae, probably an unnatural association of genera which have assumed a free discoidal form of zoarium, they may reach a very high degree of development, but Busk's suggestion that in this group they "may be subservient to locomotion" needs verification.