368 WILLIAM A. HILTON 
3! 
Fig. 28 Diagram of the circulation of the blood in a Desmognathus about 12 
mm. long, and before hatching. 
Fig. 29. Sketch of a Desmognathus embryo just before hatching, showing the 
direction of flow in the blood vessels at a time when the first parallel has been 
formed.  X 5. 
Fig. 30 Sketch of vessels in a larva of Desmognathus just after hatching, hav- 
ing three parallel systems of vessels and a central yolk vessel. 5. 
Fig. 31 Diagram of the flow of blood in the central portion of the cutaneous 
system of a Desmognathus larval4mm. long. The head end is at the right. The 
heavy vessel is a part of the lateral cutaneous. The dotted area is the pigmented 
edge of the body-wall. Two parallel vessels with their perpendiculars are shown. 
