Editing Butterfly (section)

====Eggs====

[[File:2012-06-27 Aporia crataegi eggs Malus domestica.JPG|thumb|Eggs of black-veined white (''[[Aporia crataegi]]'') on [[apple]] leaf]]
[[File:Butterfly laying eggs underneath a leaf.jpg|thumb|A butterfly from the genus ''[[Euploea]]'', laying eggs underneath the leaf]]

Butterfly eggs are protected by a hard-ridged outer layer of shell, called the ''chorion''. This is lined with a thin coating of wax which prevents the egg from drying out before the larva has had time to fully develop. Each egg contains a number of tiny funnel-shaped openings at one end, called ''micropyles''; the purpose of these holes is to allow sperm to enter and fertilize the egg. Butterfly eggs vary greatly in size and shape between species, but are usually upright and finely sculptured. Some species lay eggs singly, others in batches. Many females produce between one hundred and two hundred eggs.<ref name=Capinera640>{{cite book |author=Capinera, John L. |title=Encyclopedia of Entomology |url=https://books.google.com/books?id=i9ITMiiohVQC&pg=PA640 |year=2008 |publisher=Springer Science & Business Media |isbn=978-1-4020-6242-1 |page=640 |access-date=8 January 2016 |archive-date=20 May 2016 |archive-url=https://web.archive.org/web/20160520021643/https://books.google.com/books?id=i9ITMiiohVQC&pg=PA640 |url-status=live }}</ref>

Butterfly eggs are fixed to a leaf with a special glue which hardens rapidly. As it hardens it contracts, deforming the shape of the egg. This glue is easily seen surrounding the base of every egg forming a meniscus. The nature of the glue has been little researched but in the case of ''[[Pieris brassicae]]'', it begins as a pale yellow granular secretion containing acidophilic proteins. This is viscous and darkens when exposed to air, becoming a water-insoluble, rubbery material which soon sets solid.<ref>{{cite journal |author1=Beament, J.W.L. |author2=Lal, R. |year=1957 |title=Penetration Through the Egg-shell of ''Pieris brassicae'' |journal=Bulletin of Entomological Research |volume=48 |issue=1 |pages=109–125 |doi=10.1017/S0007485300054134}}</ref> Butterflies in the genus ''[[Agathymus]]'' do not fix their eggs to a leaf; instead, the newly laid eggs fall to the base of the plant.<ref name=Scott121>{{cite book |author=Scott, James A. |title=The Butterflies of North America: A Natural History and Field Guide |url=https://books.google.com/books?id=Oa5m8gZcGjMC&pg=PA121 |year=1992 |publisher=Stanford University Press |isbn=978-0-8047-2013-7 |page=121 |access-date=8 January 2016 |archive-date=18 May 2016 |archive-url=https://web.archive.org/web/20160518162206/https://books.google.com/books?id=Oa5m8gZcGjMC&pg=PA121 |url-status=live }}</ref>

Eggs are almost invariably laid on plants. Each species of butterfly has its own host plant range and while some species of butterfly are restricted to just one species of plant, others use a range of plant species, often including members of a common family.<ref>{{cite book |author=Capinera, John L. |title=Encyclopedia of Entomology |url=https://books.google.com/books?id=i9ITMiiohVQC&pg=PA676 |year=2008 |publisher=Springer Science & Business Media |isbn=978-1-4020-6242-1 |page=676 |access-date=8 January 2016 |archive-date=2 May 2016 |archive-url=https://web.archive.org/web/20160502065723/https://books.google.com/books?id=i9ITMiiohVQC&pg=PA676 |url-status=live }}</ref> In some species, such as the [[great spangled fritillary]], the eggs are deposited close to but not on the food plant. This most likely happens when the egg overwinters before hatching and where the host plant loses its leaves in winter, as do [[Viola (plant)|violets]] in this example.<ref name=Shepard55>{{cite book |author1=Shepard, Jon |author2=Guppy, Crispin |title=Butterflies of British Columbia: Including Western Alberta, Southern Yukon, the Alaska Panhandle, Washington, Northern Oregon, Northern Idaho, and Northwestern Montana |url=https://books.google.com/books?id=il6rJ7glHNQC&pg=PA55 |year=2011 |publisher=UBC Press |isbn=978-0-7748-4437-6 |page=55 |access-date=8 January 2016 |archive-date=13 May 2016 |archive-url=https://web.archive.org/web/20160513010746/https://books.google.com/books?id=il6rJ7glHNQC&pg=PA55 |url-status=live }}</ref>

The egg stage lasts a few weeks in most butterflies, but eggs laid close to winter, especially in temperate regions, go through a [[diapause]] (resting) stage, and the hatching may take place only in spring.<ref>{{cite web |title=British Butterflies: Education: Butterflies in Winter |url=http://www.britishbutterflies.co.uk/winter.asp |access-date=12 September 2015 |archive-url=https://web.archive.org/web/20170107044348/http://www.britishbutterflies.co.uk/winter.asp |archive-date=7 January 2017 |url-status=dead }}</ref> Some temperate region butterflies, such as the [[Nymphalis antiopa|Camberwell beauty]], lay their eggs in the spring and have them hatch in the summer.<ref>{{cite web |title=Camberwell Beauty |url=http://www.luontoportti.com/suomi/en/perhoset/camberwell-beauty |publisher=NatureGate |access-date=12 September 2015 |archive-url=https://web.archive.org/web/20170421061806/http://www.luontoportti.com/suomi/en/perhoset/camberwell-beauty |archive-date=21 April 2017 |url-status=dead }}</ref>