1、12Butterfly is an insect of the order Lepidoptera. Unlike many insects, butterflies do not experience a nymph period, but instead go through a pupal (蛹的）蛹的）stage which lies between the larva（幼虫）（幼虫） and the adult stage (the imago成虫成虫). Butterflies are termed as holometabolous（完全变态（完全变态 ）insects, and
2、 go through complete metamorphosis(变态）变态）.31.Egg2.Larva, known as a caterpillar 3.Pupa (chrysalis) 4.Adult butterfly (imago) 45Butterfly eggs consist of a hard-ridged outer layer of shell, called the chorion(绒毛膜）. This is lined with a thin coating of wax（蜡） which prevents the egg from drying out bef
3、ore the larva has had time to fully develop. Each egg contains a number of tiny funnel-shaped openings at one end, called micropyles（卵孔）（to allow sperm （精子）to enter and fertilize the egg）. Butterfly eggs are fixed to a leaf with a special glue which hardens rapidly and will deform the shape of the e
4、gg.6Eggs are usually laid on plants. Each species of butterfly has its own hostplant range and while some species of butterfly are restricted to just one species of plant.7The egg stage lasts a few weeks in most butterflies but eggs laid close to winter, especially in temperate regions, go through a
5、 diapause(滞育） stage, and the hatching （孵卵）may take place only in spring. Other butterflies may lay their eggs in the spring and have them hatch in the summer（northern species ）. 89Butterfly larvae, or caterpillars, consume plant leaves and spend practically all of their time in search of food. Altho
6、ugh most caterpillars are herbivorous(plant eating), a few species are entomophagous (insect eating).10Butterfly caterpillars have three pairs of true legs from the thoracic (胸）胸）segments and up to 6 pairs of prolegs arising from the abdominal（腹部）（腹部） segments. 1112Wings or wing pads（翅芽） are not vis
7、ible on the outside of the larva, but when larvae are dissected(切开）, tiny developing wing disks can be found on the second and third thoracic segments, in place of the spiracles (呼吸孔）that are apparent on abdominal segments . Wing disks are very small until the last larval instar .13蝶蛹蝶蛹1415The larva
8、 transforms into a pupa (or chrysalis蛹) by anchoring（依靠） itself to a substrate（基质） and moulting （换毛）for the last time. The chrysalis is usually incapable of movement.The pupal transformation into a butterfly through metamorphosis（变态） has held great appeal to mankind. To transform from the miniature
9、wings visible on the outside of the pupa into large structures usable for flight, the pupal wings undergo rapid mitosis（有丝分裂） and absorb a great deal of nutrients. 1617The adult is sexually mature. As Lepidoptera, butterflies have four wings that are covered with tiny scales .The fore and hindwings
10、are not hooked together, permitting a more graceful flight. An adult butterfly has six legs, but in the nymphalids, the first pair is reduced. After it emerges from its pupal stage, a butterfly cannot fly until the wings are unfolded. A newly-emerged butterfly needs to spend some time inflating its
11、wings with blood and letting them dry, during which time it is extremely vulnerable to predators. 18Butterflies feed primarily on nectar(花蜜）花蜜） from flowers. Some also derive nourishment from pollen（花（花粉），粉），tree sap（汁）（汁）, rotting fruit, dung（家畜粪便）（家畜粪便）, and dissolved minerals in wet sand or dirt.
12、 Butterflies are important as pollinators （传（传粉媒介）粉媒介）19As adults, butterflies consume only liquids and these are sucked by means of their proboscis（喙）. They feed on nectar from flowers and also sip water from damp patches. This they do for water, for energy from sugars in nectar and for sodium（钠） a
13、nd other minerals which are vital for their reproduction. Several species of butterflies need more sodium than provided by nectar. They are attracted to sodium in salt and they sometimes land on people, attracted by human sweat. Besides damp patches, some butterflies also visit dung, rotting fruit or carcasses（躯体） to obtain minerals and nutrients. 20写在最后写在最后成功的基础在于好的学习习惯成功的基础在于好的学习习惯The foundation of success lies in good habits21谢谢大家荣幸这一路，与你同行ItS An Honor To Walk With You All The Way讲师：XXXXXX XX年XX月XX日
