PRIMITIVE EMBRYONIC BODY FORM LARVAL BODY FORM 



DEFINITIVE BODY FORM 



Fig. 255. This figure illustrates different types of body form in various vertebrates 

 during embryonic development. A, D, H, M, and Q show primitive embryonic body 

 form in the developing shark, rock fish, frog, chick, and human. B, larval form of 

 shark; E and F, larval forms of rock fish; I and J, larval forms of frog; N and O, larval 

 forms of chick; R, larval form of human. C, G, K, L, P, and S represent definitive 

 body form in the above species. (Figures on rockfish development (Roccus saxatilis) re- 

 drawn from Pearson: 1938, Bull. Bureau of Fisheries, U. S. Dept. of Commerce, vol. 

 49; figures on chick redrawn from Hamburger and Hamilton: 1951, J. Morphol., vol. 

 88; figure Q, of developing human embryo, redrawn and modified from model based 

 upon Normentafein of Keibel and Elze: 1908, vol. 8, G. Fischer, Jena; Dimensions of 

 human embryos in R and S, from Mall: Chap. 8, vol. I, Human Embryology, by 

 F. Keibel and F. P. Mall, 1910, Lippincott, Philadelphia.) 



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