United States or Romania ? Vote for the TOP Country of the Week !
And often they exist in one kind of animal without doing any harm, and are only poisonous when introduced by insects into the blood of other kinds of animals! There is, further, another set of disease-causing protozoan parasites which are similar to the amoeba or proteus-animalcule, and a third, which belong to the group of "ciliated infusoria."
By subjecting the cilia to the action of iodine, their motion is arrested, they are stained brown, and become very plainly visible. Eminent English authorities have advanced the theory that the ciliated gonidium of Vaucheria is in reality a densely crowded aggregation of biciliated zoospores, similar to those found in many other confervoid algæ.
This important fact justifies us in concluding, in accordance with the biogenetic law, that their ancestors also were phylogenetically developed from a similar stem-form. This ancient stem-form is the gastraea. The gastraea probably lived in the sea during the Laurentian period, swimming about in the water by means of its ciliary coat much as free ciliated gastrulae do to-day.
The young girl uttered a cry of childish delight, as the soft ciliated fibres touched her sensitive skin. "It is healing, too," continued Low; "a moccasin filled with it after a day on the trail makes you all right again." But Miss Nellie seemed to be thinking of something else. "Is that the way the squaws bathe and dry themselves?" "I don't know; you forget I was a boy when I left them."
Our eye makes use of light in that it enables us to utilize, by movements of reaction, the objects that we see to be advantageous, and to avoid those which we see to be injurious. Now, of course, as light may have produced a pigment-spot by physical means, so it can physically determine the movements of certain organisms; ciliated Infusoria, for instance, react to light.
After the secretion passes through the tortuous coils of ciliated tubes of the epididymis, it is collected into a single tube called the vas deferens, which passes as a part of the spermatic cord from the scrotum, up through the groin and over the pubic arch into the pelvic cavity, passing down back of the bladder where it is slightly dilated into an ampulla, beyond which the duct is again contracted into a narrow tube, and the two ducts, one from either side, converge and pass into the prostate gland, where they empty into the urethra.
We still find, both in the sea and in fresh water, various kinds of primitive multicellular organisms that substantially resemble the blastula in structure, and may be regarded in a sense as permanent blastula-forms hollow vesicles or gelatinous balls, with a wall composed of a single layer of ciliated homogeneous cells.
A notice of the ciliated germs of Flustra, communicated to the Plinian Society in 1826, was the first fruits of Darwin's half century of scientific work. Occasional attendance at the Wernerian Society brought him into relation with that excellent ornithologist the elder Macgillivray, and enabled him to see and hear Audubon.
They are only 1/250 of an inch in diameter, and thus are only half the size of the mammal ova, and have no distinctive features. Fecundation takes place when these lively ciliated cells of the sperm approach the ovum, and seek to penetrate into the yelk-matter or the cellular substance of the ovum with their head-part the thicker part of the cell that encloses the nucleus.
In this family the body is long and slender, and the segments much alike in size. There is a pair of spiracles on each thoracic ring. The maxillæ are comb-shaped, due to the four slender, minutely ciliated spines placed within the outer tooth. The labium in Japyx is four-lobed and bears a small two-jointed palpus.
Word Of The Day