I believe this is true of all reptiles with live births. most fish as well, however I think some sharks are actually placental.... or something close

that would be a big egg for a shark, well depending on the size
acutally, back home my bf and I bought a shark egg for our saltwater aquarium. it was more of like a capsule than an egg. it was a banded cat shark. so I guess it depends on the shark.

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0.0.2 painted turtles (Mo and Squirt)
1.0.0 yellow bellied slider (Jebidiah)
0.1.0 Amelanistic corn snake (Rose)
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most species that give live birth (which would normally be egg layers) will develope the eggs within them and the eggs will hatch just before birth, and you get live young. there are some sharks that do this too, but what I was saying was that I think some sharks may have something similar to a placenta, because when born they have a cord still attached going to their stomachs...... this could still be something from within the egg though..... but normally when an animal hatches this has been fully absorbed.

anyways, sorry for the hijack

All sharks go through an egg-like embryonic stage. The eggs are generally small, and the little shark that hatches first eats all the rest as it grows, when it is actually birthed it is considerably larger than when it hatched. Most of these type sharks have two offspring per year.

The capsule that was mentioned is an egg case, that is quite possibly one of the coolest things to see. It is actually living nerve tissue and can mount itself to the substrate and in the case of skates, can actually maneuver slightly to the best possible attaching point. The reason the eggs are in a leathery case instead of a shell is to survive the potentially turbid environment and to stretch allowing the shark to move easier in the case. The egg case you bought is more commonly called a bamboo shark, or brown banded bamboo shark, Chiloscyllium punctatum.

The cord that you are speaking of is generally what is left of the yolk. There are some exceptions to this, but they are very rare, and in research phases since there is not much known about them and the birth process is still difficult to be 100% sure of.

As for the snake, a smaller prey item may be more readily accepted, try scaling down slightly so that it is not a strain to ingest or digest.

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TKE:TT:118

And some skinks actually do have placental live birth.

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