Carnegie Stage 17

Introduction

Stage 17 embryos have a greatest length of 11 to 14 mm and an estimated post-fertilization age of 41 days. Hand rays have formed and the auricular hillocks are distinct. The stage is represented by Carnegie embryo #6520. It has a corrected greatest length of 14.2 mm (after fixation). The specimen is considered to be median within the stage.

New structures include C-1 vertebra (atlas), carotid arteries, cartilage, intercostal muscles, mammary gland, parathyroid gland, ribs, tertiary bronchopulmonary buds, thymus gland.

Also on EHD: Touching Thumbs

Surface

Lateral view of embryo No. 6520 after fixation