chorioallantoic placenta

https://doi.org/10.1351/goldbook.10515

Placenta developed from the allantois and chorion, establishing a nutritive and excretory connection between the blood of the fetus and that of the mother.

Source:
PAC, 2016, 88, 713. (Glossary of terms used in developmental and reproductive toxicology (IUPAC Recommendations 2016)) on page 735 [Terms] [Paper]