Mouth cavity:
- Floor of foregut (Endoderm)
- Stomodeum (Ectoderm)
In between is the Buccopharyngeal membrane which ruptures at the end of the 3rd week

Salivary glands
1. Parotid gland: Ectodermal
- Ectodermal groove appears behind the angle of the mouth
- Closes to form the parotid duct
- Branches repeatedly and canalizes to form acini
- Duct recedes from the angle of the mouth
- Duct opens in vestibule, opposite maxillary 2nd molar
2. Submandibular gland: Endodermal
- Endodermal groove appears between tongue and gums
- Closes to form submandibular duct
- Branches repeatedly and canalizes to form acini
- Anterior end of duct proceeds forwards , and opens close to frenulum of tongue
3. Sublingual gland: Endodermal
- Arise as small buds from submandibular groove
- Attain common sheath
- Has several openings in floor of mouth
Clinicals:
- Cyst formation – Lymphoepithelial cysts/branchial cysts commonly found in the anterior triangle of the neck
- Agenesis (failure to develop) of gland
- Atresia (no canalization) of duct