[WRIGHT] AN EARLY ANADIDYMUS OF THE CHICK ' 25 



In conclusion, in spite of the apparent posterior simplicity of thia 

 embryo I am of the opinion that it can best be explained by assuming 

 a double gastrulation at points very close to each other on the surface 

 of the embryonic area. 



LiTER.\TURE Cited. 



I have thought it unnecessary to cite all the papers consulted. 

 Hertwig (No. 3) and Kaestner (No. G) give a full list of papers to 

 some of which, unfortunately, I have not had access. 



No. 1. Duval — Atlas d'Eml:)ryologie. 



No. 2. Dareste — Production des Monstruosités. 



No. 3. Hertwig — Handbuch der Entwickelungslehre. 



No. 4. Hoffmann — Arch. mikr. Anat. XLI. 



No. 5. Kaestner, Arch. Anat. Phys., '98. 



No. 6. Kaestner, Arch. Anat. Phys., '02. 



