1. Just where was the insect found?
  2. Note carefully what the insects are doing before they are disturbed by your presence. What did the insects do when you disturbed them? If you think this related to securing safety, explain what leads you to think so.
  3. What senses do you conclude are well developed? Reason for your conclusion.
  4. Has the insect a home? If so, what is its character?
  5. What is the color? What is the relation between the color of the insect and its surroundings?
  6. Is the insect solitary in its habits or associated with others of the same species? If in association with others, note the numbers, and what they are doing.
  7. What modes of locomotion do you observe in this insect? Which is the most common? If it flies or jumps, note the distance.
  8. If you find the young, note whether they differ from the adult in general appearance, and if so, in what ways they differ. Do they differ in food?
  9. What other insects do you find in the same habitat?

2. A STUDY OF GRASSHOPPERS (LOCUSTS)

Insects adapted to Life in Grassy Meadows and Fields

Materials.

Both living and dead specimens of grasshoppers. Various stages of young grasshoppers either dead or living. Some mounted specimens with wings spread. The wings of grasshoppers mounted in pairs between two glass slides for use with microscope or hand lens. Mounted preparations of mouth parts and tracheæ.

Definitions.

Orthoptera, straight-winged insects, order to which belong grasshoppers, locusts, katydids, crickets, cockroaches, etc. Vivarium, a cage in which living animals are kept. Anterior, toward the head of an animal. Posterior, opposite to anterior. Dorsal, the upper surface of an animal. Ventral, opposite to dorsal. Regions, principal divisions of the body of an animal. Head, thorax, and abdomen, the three distinct regions into which the body of a grasshopper is divided. Somite, a ring-like division of the body of an animal. Prothorax, mesothorax, and metathorax, the three divisions or somites into which the thorax of any insect is divided. A pair of legs is borne on each division. Exoskeleton, an external skeleton. Femur, tibia, and tarsus, the three principal divisions of the leg corresponding to thigh, shank, and foot. Veins, thread-like thickenings of the wings. Ocelli, the single or simple eyes of an insect, composed of a single eye element. Compound eyes, made up of many eye elements. Auditory sacs, organs for hearing in many animals. Antennæ, the feelers borne on the head. Labrum, the upper lip. Labium, the lower lip, formed by the growing together of the second maxillæ. Mandibles, primary jaws situated under the labrum. Maxillæ, secondary jaws just in front of the labium, each composed of three parts, a palp, a spoon, and a tooth. Palps, the jointed finger-like structures used to handle food, one pair on the labium and one pair on the maxillæ. Spiracles, openings into the trachea found along the sides of the abdomen and thorax. Tracheæ, slender tubes used for breathing organs among insects. They carry the air direct to the tissues in all parts of the body. Ovipositors, structures on the posterior end of the abdomen of a female, used to deposit eggs. Metamorphosis, refers to the development of the young of animals when striking changes in structure occur in the course of their growth. Metamorphosis is called complete when the young have no resemblance to the adults, and incomplete when there is a resemblance to the adult. In complete metamorphosis the stages are larva, pupa, and adult. In incomplete metamorphosis the stages are nymph and adult.

Observations.

The Body.

  1. Show how the shape of the grasshopper's body is well adapted to its needs.
  2. Which region of the body is the thickest? What seems to be the reason for this? Which regions are capable of movement?