The larvae are elongate and worm-like, with short legs but often with hard strong cuticle.
The footless larvae are elongate, worm-like and very active; they feed upon almost any kind of waste animal matter, and when full-grown form a silken cocoon.
The fore-legs are elongate and adapted for clasping, while the short and flattened intermediate and hind legs form very perfect oar-like propellers.
With very few exceptions, the larva in this group is active and campodeiform, with cerci and elongate legs as in the Adephaga, but the leg has only four segments and one claw.
The larvae of the beautiful, elongate, metallic Donaciae live in the roots and stems of aquatic plants, obtaining thence both food and air.
The head of an ant carries a pair of elbowed feelers, each consisting of a minute basal and an elongate second segment, forming the stalk or "scape," while from eight to eleven short segments make up the terminal "flagellum."
These segments are abundantly supplied with elongate tooth-like projections connected with nerve-endings probably olfactory in function.
In most insects the leg is built up of nine segments: (1) a broad triangular, sub-globular, conical or cylindrical haunch (coxa); (2) a small trochanter; (3) an elongate stout thigh (femur); (4) a more slender shin (tibia); and (5-9) a foot consisting of five tarsal segments.
The scales are sometimes rounded behind, but generally rhombic in shape and more or less elongate; they may be quite smooth or provided with a longitudinal ridge or keel in the middle line.
They are recognizable by their slender and elongate hind-legs; many of them provision their burrows with spiders.
The " tongue," for example, is short and obtuse or emarginate in Colletes and Prosopis, while in all other bees it is pointed at the tip. But in Andrena and its allies it is comparatively short, while in the higher genera, such as A pis and Bombus, it is elongate and flexible, forming a most elaborate and perfect organ for taking liquid food.
The Capsidae are a large family of rather soft-skinned bugs mostly elongate in form with the two basal segments of the feelers stouter than the two terminal.
Another genus has been described from the Pleistocene of Nebraska, as Paramylodon; it has only four pairs of teeth, and an elongate skull with an inflated muzzle.
The motions of these limbless lizards are similar to those of snakes, which they resemble in their elongate body.
The skeleton is cartilaginous, and the skull is remarkable for the very elongate suspensorium of the lower jaw; the tail remains in the notochordal condition, no cartilages being formed in this organ, which is destined to disappear with the gills.
In the Algae, such as Fucus, Volvox, Oedogonium, Bulbochaete, and in the Fungus Monoblepharis, the spermatozoid is a small oval or elongate cell containing nucleus, cytoplasm and sometimes plastids.
The prothorax is convex in front, and is usually drawn out behind into a prominent process on either side, while the elytra are elongate and tapering.
The larvae of Elateridae are elongate, worm-like grubs, with narrow bodies, very firm cuticle, short legs, and a distinct anal proleg.
The Cerambycidae, or longhorn beetles, are recognizable by their slender, elongate feelers, which are never clubbed and rarely serrate.
It is customary to divide the Orthorrhapha into the two divisions Nematocera and Brachycera, in the former of which the antennae are elongate and in a more or less primitive condition, as described above, while in the latter these organs are short, and, as already explained, apparently composed of only three joints.
The majority have a compressed well-proportioned body, which in the marine species is of a more elongate form, leading to the allied group of flute-mouths (Fistulariidae), which are, in fact, gigantic marine sticklebacks.
The feelers are elongate and conspicuous.
The larvae are remarkable for their small head, very broad thorax, with reduced legs, and narrow elongate abdomen.
In some of the species the elongate form of the head is still more exaggerated by a pointed flexible appendage of the snout (Passerita), which may be nearly half an inch in length, or leaf-like, as in the Madagascar Langaha.
The Siricidae (" wood-wasps ") are large elongate insects also with one spine on each fore-shin, but with the pronotum closely joined to the mesothorax.
Owing to more or less herbivorous habits, the intestine is exceedingly elongate and much convoluted, being several times larger and of a greater calibre than after the metamorphosis.
What characterizes a tadpole is the conjoined globular head and body, so formed that it is practically impossible to discern the limit between the two, sharply set off from the more or less elongate compressed tail which is the organ of propulsion.