PLATE VII. 

 Figure G. Magnification about 10 d. 



Drawing- from a reconstruction of Embryo XXII; length, 20 mm.; age, 

 about 7 weeks (see also Figs. F, H and I). The left arm was not recon- 

 structed, but has been drawn in part from the reconstruction of the right 

 arm, in part from a photograph. In the region of the right arm the 

 pectoralis major, biceps, coraco-brachialis, brachialis, brachio-radialis, ex- 

 tensor carpi radialis longus et brevis, the extensor communis digitorum and 

 extensor carpi ulnaris; and the interossenis muscles may be seen. In the 

 abdominal region the external oblique and rectus muscles are exposed. In 

 the region of the posterior limb the adductor and ham-string muscles, and 

 the tibialis anticus, the extensor pollicis longus and extensor digitorum 

 communis muscles may be distinguished. The ventral tips of the thoracic 

 nerves and the long saphenus nerve, and the tip of the anterior tibial nerve 

 are shown. 



The dense mesenchyme covering the cartilaginous parts of the skeleton 

 is pictured intact. 



