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===Bullhead sharks===
Bullhead shark egg cases are shaped like an [[Auger (drill)|auger]], with two spiral flanges. This allows the egg cases to become wedged in the crevices of rocky sea floors, where the eggs are protected from predators; however, some bullhead sharks deposit their eggs on sponges or seaweed.<ref>{{Cite web|url=https://www.floridamuseum.ufl.edu/fish/discover/species-profiles/heterodontus-francisci/|title=Heterodontus francisci|last=Buch|first=Robert|website=Florida Museum}}</ref><ref name=":2">{{Cite journal|last=Compagno|first=Leonard|date=2002|title=Sharks of the World|journal=FAO Species Catalogue for Fishery Purposes|volume= 2|pages=31–50}}</ref> Hatchlings are considered large for sharks, reaching over 14 cm in length by the time they leave the egg case.<ref name=":2" /> Bullhead shark eggs typically hatch after 7 to 12 months, depending on the species.<ref name=":2" /> The female [[Japanese bullhead shark]] has been known to deposit their eggs in one location along with other females, called a "nest".<ref name=":2" /> The egg case of the [[Mexican hornshark]] features a tendril and more rigid flanges, suggesting that egg case design of this species is evolving towards anchoring with tendrils and away from wedging into crevices.<ref name=":2" /> As a member of the order Heterodontiformes, the [[whitespotted bullhead shark]]s
[[File:Chiloscyllium punctatum egg sunshine international.jpg|thumb|upright=0.8|Egg case of a [[brownbanded bamboo shark]]]]
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=== Big skate ===
Big skate egg cases are larger than most other skate egg cases; typically ranging from 210 to 280 mm in length and 110 to 180 mm in width.<ref name="Ebert2"/><ref name="
Big skates are one of only two skates known to have multiple embryos inside an egg case; up to 7 embryos have been found inside a single case. But most big skate egg cases contain 3–4 embryos.<ref name="Ebert, D.A., Smith, W.D., and Cailliet, G.M. (2008)2">Ebert, D.A., Smith, W.D., and Cailliet, G.M. (2008). "Reproductive biology of two commercially exploited skates, ''Raja binoculata'' and ''R. rhina'', in the western Gulf of Alaska". ''Fisheries Research'', 94:48-57. {{doi|10.1016/j.fishres.2008.06.016}}</ref>
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