Accueil / Albums / Résultats de recherche 210
Choisir les filtres
Annuler
Valider
Choisir les filtres
Valider
Valider
Valider
- Xenopsylla cheopis, male
- Wreathed Weaving Spider
The Wreathed Weaving Spider ( Theridium redimitum), which occurs quite commonly, especially in gardens, becomes at most 5 mM. long; this fat little spider inhabits all kinds of low-growing herbs and shrubs; here it spins (fig. 1) a few leaves together by irregularly oriented threads, on which the small animals that make up its food stick to. The mother attaches the spherical, bluish egg sac to a leaf (fig. 2), keeps watch next to it until the young have hatched, and continues to do so for the few days of their cohabitation. These beautiful spiders are very variable in color and drawing. Transparent and almost white in their early youth, spotted black only on the back of the abdomen; towards the end of June, in July and in August, they have taken on a pale yellow color, some plain, others with a stain on the abdomen, which can be pure pinkish red or partially greenish, circular or oval. In addition, the rim and a line across the center of the head-breast, 6 pairs of round dots on the abdomen, the tip of the probes and the shins are black. grab. [As translated from the Dutch by online translator ] - Wandering Crab Spider
Wandering Crab Spider ( Thomisus viaticus ): in the background a specimen, which ejects a thread and another, which is suspended by the wind while hanging on a thread; in the foreground a male, b a female and c the eye-bearing part of the head-breast seen from behind. - Violacea Butterfly
Larva, Protected by Ants, Feeding on Flower-buds of Dogwood. Why this species, and doubtless many others of its family, are thus favored, will soon be apparent. Ants may be seen wherever these larvæ may be found, ever ready to receive the honeyed secretion when it pleases the little creatures to eject it, but all the while exercising the closest vigilance lest some wary ichneumon may come along and deal a thrust of its ovipositor, which means misery and ultimate death to their helpless friends. So intent is the larva, with its head buried in the flower, upon its feeding, and so quietly and stealthily does the ichneumon approach its intended victim, that hardly a single individual would be left to tell the story of its existence were it not for the ants. The larvæ know their protectors, it would seem from their actions, and are able and willing to reward their services. The advantage is mutual, and the association friendly. No compelling by rough means on the one part is noticeable, and no reluctant yielding on the other. All demonstrations made by the ants are of the most gentle character. They caress, entreat, and as they drink in the sweet fluid, lifting their heads to prolong the swallowing, they manifest to the utmost their satisfaction and delight. It is amusing to see them lick away the last trace, caressing the back of the segment with their antennæ as they do so, as though they were coaxing for a little more. - Upper Side of Epeira Vulgaris
The head is not separated from the rest of the body, as in insects, but forms, with the thorax, one piece. On the front of the head are eight eyes, Q, which are differently arranged in different spiders. On the abdomen are several pairs of dark smooth spots, which mark the ends of muscles extending downward through the abdomen. The markings of this spider are very complicated. The spot on the middle of the front of the abdomen is a very common one, and, in some spiders, extends the whole length of the body. The waved lines on each side are also common, and, in long-bodied spiders, often form two bright-colored stripes, or rows of spots, running nearly straight the whole length of the abdomen. - Two common centipedes
- Two birds watching a bug
- Trypanosoma brucei
By trypanosomiasis is meant a condition of animal parasitism, common to man and the lower animals, in which trypanosomes, peculiar flagellate protozoa, infest the blood. Depending upon the species, they may be harmless, producing no appreciable ill-effect, or pathogenic, giving rise to conditions of disease. A number of these are known to be transferred by insects. The trypanosomes are elongated, usually pointed, flagellated protozoa in which the single flagellum, bent under the body, forms the outer limit of a delicate undulating membrane. It arises near one end of the organism from a minute centrosome-like body which is known as the blepheroplast, and at the opposite end extends for a greater or less distance as a free flagellum. Enclosing, or close beside the blepheroplast is the small kinetonucleus. The principal nucleus, round or oval in form, is situated near the center of the body. Asexual reproductions occurs in this stage, by longitudinal fission, the nucleus and the blepheroplast dividing independently of one another. From the blepheroplast of one of the daughter cells a new flagellum is formed. - Thirteen-Spotted Lady Beetle
- The yellow fever mosquito (Aëdes calopus)
- The Pursuit
Birds chasing insects - The Locust
Sometimes millions of locusts come upon the wind, and devour every green thing, so that nothing is left for man or beast. - The Italian tarantula
- The house or typhoid fly (Musca domestica)
The house-fly breeds by preference in horse manure. Indeed, It has been found that they would develop in almost any fermenting organic substance. Thus, they have been bred from pig, chicken, and cow manure, dirty waste paper, decaying vegetation, decaying meat, slaughter-house refuse, sawdust-sweepings, and many other sources. A fact which makes them especially dangerous as disease-carriers is that they breed readily in human excrement. - The common round-web spider, Epeira vulgaris of Hentz (Under Side)
The body is seen to be divided into two parts, connected only by the narrow joint, A, just behind the last pair of legs. The front half of the body, called the thorax, contains the stomach, the central part of the nervous system, and the large muscles which work the legs and jaws. The hinder half, the abdomen, contains the intestine, the breathing-organs, the principal circulating-vessels, the organs of reproduction, and the spinning-organs. Connected with the thorax are six pairs of limbs, four pairs of legs, B B B B, a pair of palpi, C, and a pair of mandibles, D. - The cockroach mite
The cockroach mite, Pimeliaphilus podapolipophagus - The cattle tick (Boophilus annulatus). (a) Female; (b) male
- The Caterpillar of the Small Elephant Hawk-moth (Chærocampa porcellus)
- The Caterpillar of the Marbled White Butterfly (Arge galathea)
- The Caterpillar of the Eyed Hawk-Moth (Smerinthus ocellatus)
- The Caterpillar of the Elephant Hawk-Moth (Chærocampa elpenor). Third Stage
- The Caterpillar of the Elephant Hawk-Moth (Chærocampa elpenor). Second Stage
- The Caterpillar of the Elephant Hawk-Moth (Chærocampa elpenor). Just before the second moult.
- The Caterpillar of the Elephant Hawk-Moth (Chærocampa elpenor). Full grown
- The Caterpillar of the Elephant Hawk-Moth (Chærocampa elpenor). Fourth Stage
- The Caterpillar of the Elephant Hawk-Moth (Chærocampa elpenor). First stage
- The Caterpillar of the Elephant Hawk-Moth (Chærocampa elpenor). Fifth Stage
- Tarantula Apuliae
Apulian Tarantula ( Tarantula Apuliae ): Male - Tarantula
Tarantula ( Mygale ). - Syrian Ants
The Ant is mentioned twice in the Old Testament, both times in the Book of Proverbs (vi. 6 and xxx. 25). Ants are characterized as being exceeding wise, and in both passages are commended for their diligence in preparing their food in the summer, thus by their fore-sight providing for their winter sustenance. Such is at least the` obvious implication contained in the text. This habit was, and is still, contradicted by some writers, from their knowledge of the ways of European ants, which are dormant in the winter, and therefore stand in no need of food. - Stomoxys calcitrans - adult, larva, puparium and details
Stomoxys calcitrans, the stable-fly—It is a popular belief that house-flies bite more viciously just before a rain. As a matter of fact, the true house-flies never bite, for their mouth-parts are not fitted for piercing. The basis of the misconception is the fact that a true biting fly, Stomoxys calcitrans , closely resembling the house-fly, is frequently found in houses and may be driven in in greater numbers by muggy weather. From its usual habitat this fly is known as the "stable-fly" or, sometimes as the "biting house-fly." - Sting of a honey bee
- Stethaspis suturalis - Larva
Stethaspis suturalis - Larva - Stethaspis suturalis
Stethaspis suturalis - Staphylinus oculatus
Staphylinus oculatus - Stages of the Diamond-back Moth
a, Diamond-back Moth (Plutella cruciferarum) b, young caterpillar, dorsal view c, full-grown caterpillar, dorsal view d, side view e, pupa, ventral view. From Journ. Dept. Agric. Ireland, vol. I - Spirochæta gallinarum. After Hindle.
Spirochætosis of Fowls—One of the best known of the spirochætes transmitted by arthropods is Spirochæta gallinarum, the cause of a very fatal disease of domestic fowls in widely separated regions of the world. According to Nuttall, it occurs in Southeastern Europe, Asia, Africa, South America and Australia. In 1903, Marchoux and Salimbeni, working in Brazil, made the first detailed study of the disease, and showed that the causative organism is transmitted from fowl to fowl by the tick Argas persicus. They found that the ticks remained infective for at least five months. Specimens which had fed upon diseased birds in Brazil were sent to Nuttall and he promptly confirmed the experiments. - Spiny Spider
In the specimen on the tree trunk, the spider field is seen protruding like a glittering black nodule in the middle of the transversely wrinkled underside of the bright blood-red abdomen, which, in addition to the 2 long, curved thorns at the rear corners, bears 2 pairs of shorter spines, which as the spots on the back are black. The front part of the body is hairy and glossy black. - Spiderweb
The simple nests and tubes that have been described are made by spiders, most of which spin no other webs. The larger and better known cobwebs for catching insects are made by comparatively few species. On damp mornings in summer the grass-fields are seen to be half covered with flat webs, from an inch or two to a foot in diameter, which are considered by the weatherwise as signs of a fair day. These webs remain on the grass all the time, but only become visible from a distance when the dew settles on them. Figure is a diagram of one of these nests, supposed, for convenience, to be spun between pegs instead of grass. The flat part consists of strong threads from peg to peg, crossed by finer ones, which the spider spins with the long hind-spinnerets - Some early medical entomology
- Simulium venustum
The Simuliidæ, or black flies, are small, dark, or black flies, with a stout body and a hump-back appearance. The antennæ are short but eleven-segmented, the wings broad, without scales or hairs, and with the anterior veins stout but the others very weak. The mouth-parts are fitted for biting. - Seventeen-year Cicada
Adult, Chrysalis-Case, Pupa, Entrances to Burrows and Egg-Nests. In the winged state Cicada septendecim is of a black color, with transparent wings and wing-covers, the thick anterior edge and veins of which being orange-red. Near the tips of the latter there is a dusky zig-zag line which resembles in shape the letter W. The eyes, when living, are also red, while the legs are a dull orange, which color is conspicuous along the edges of the rings of the body. The wings expand from two and a half to three and a quarter inches. - Sepsis violacea; puparium and adult
Sepsis violacea; puparium and adult - Section through a venom gland of Latrodectus 13-guttatus showing the peritoneal, muscular and epithelial layers
- Section of Epeira Vulgaris
Section of a spider to show the arrangement of the internal organs: a, b, upper and under lips of the mouth; c, c, the œsophagus; d, f, upper and under muscles of the sucking-stomach; e, stomach; g, g, ligaments attached to diaphragm under the stomach; J, lower nervous ganglion; k, upper ganglion; l, l, nerves to the legs and palpi; m, branches of the stomach; n, poison-gland; o, intestine; p, heart; R, air-sac; S, ovary; t, air-tube; u, spinning-glands. The intestine, o, continues backward through the abdomen to the anus, in the little knob behind the spinnerete. The brown mass which surrounds the intestine, and fills the abdomen above it, is supposed to be a secreting-organ discharging into the intestine at several points. - Sauvage's Mason Spider
Sauvage's Mason Spider ( Cteniza fodiens ) in her home (this is greatly shortened and shown cut lengthways) .— a) Placement of eyes (greatly enlarged) .— b) Cover seen from the inside. -C) Eggs. ). - Sarcoptes scabiei. Diagrammatic representation of the course in the skin of man
- Sarcoptes scabiei, male
- Sarcoptes scabiei, female
- Salivary glands of Notonecta maculata
- Representative Protozoa associated with cockroaches
Representative Protozoa associated with cockroaches. A, Monocercomonoides melolonthae, X 3094 (after Grassé). B, Coelosporidium periplanetae, X 1310 (after Sprague); trophozoite with spores and chromatoid bodies. C, Endamoeba blattae, X 273 (after Kudo); trophozoite. D, Lophomonas striata, X 330 (after Kudo). E, Lophomonas blattarum, X 660 (after Kudo). F, Retortamonas blattae, X 3094 (after Wenrich). G, Nyctotherus ovalis, X 175 (after Kudo). H, Gregarina rhyparobiae, c. X 52: mature trophozoite attached to intestinal wall of Leucophaea maderae. (Redrawn from J. M. Watson [1945].) I, Diplocystis schneideri, c. X 14.4 (after Kunstler). J, Gregarina blattarum, c. X 57 (after Kudo). K, Protomagalhaesia serpentula, X 36 (after Pinto). L, Gamocystis tenax, magnification not known (after Schneider). - Relationship between a mature plant of Herpomyces stylopygae and the integument of Blatta orientalis
Diagram illustrating the relationship between a mature plant of Herpomyces stylopygae and the integument of Blatta orientalis. Richards and Smith have studied the life history of Herpomyces stylopygae on the oriental cockroach. The plants grow only on living cockroaches, and the infection is disseminated by contact. - Reduvius (Opsicœtus) personatus
- Rasahus biguttatus
- Pupa of flea
- Pulex irritans, female
- Pterostichus opulentus - Larva
- Pterostichus opulentus
- Pseudargiolus Butterfly
Larva Feeding on Bud of Black Snakeroot, and Guarded by Ants. But now comes the most remarkable part of the larval history of Pseudargiolus. The whole upper part of the larva is covered with small, glassy, star-shaped processes, scarcely raised above the surrounding surface, from the centre of which spring short, filamentous bodies, bristling with feathery-looking tentacles, which the caterpillar has the power of protruding at will. It throws them out like the tentacles of Papilio or the horns of snails. More singular still is an opening upon the eleventh segment, placed transversely and surrounded by a raised cushion, about which the granulations that cover the body of the caterpillar are particularly dense. From the middle of this opening, which is shaped like a button-hole, issues, at the caterpillar’s will, a sort of transparent, hemispherical vesicle, from which is emitted a good-sized drop of fluid, which the animal is capable of reproducing when absorbed. - Protozoa from the gut of the wood-feeding cockroach
Protozoa from the gut of the wood-feeding cockroach Cryptocercus punctulatus. A, Eucomonympha imla, female above, male below, c. X 375. (From Cleveland [1950c].) B, Barbulanympha sp. (From Cleveland [1953].) C, Urinympha talea, c. X 712. (From Cleveland [1951a].) D, Rhynchonympha tarda, c. X 450. (From Cleveland [1952].) E, Trichonympha okolona or T. algoa, c. X 390.