260 



STUDY OF PIG EMBRYOS. 



name correctly all the parts shown in each section and to identify the distribution 

 of the three germ-layers in every case.* A sufficient number of high-power draw- 

 ings ought to be added to illustrate the character of the various tissues. 



284- 340 380 



572 



Fu;. 188. RECONSTRUCTION or A PIG EMBRYO OF 12.0 MM. WITH INDICATIONS OF THK PLANES OF -SECTIONS 



FIGURED. 

 an, Cloacal membrane. Ao, Aorta. Au, Auricle. A.um, Umbilical artery, a.v, Vertebral artery, bas, Basilar 



artery, c, Anlage of caecum, car, Internal carotid, can. Caudal artery. C.Ex, External carotid artery. 



f.b, Fore-brain. G, Spinal ganglion, g, Gall-bladder, h.b. Hind-brain. In, Intestine. Li, Liver, m.b, 



Mid-brain. o/>, Optic .vesicle. Ot, Otocyst. pan, Pancreas. Sf>, Spinal cord. St, Stomach. Urn, Umbilical 



opening. Yen, Ventricle of heart. Ill, I V, V, Aortic arches. 



284 Frontal section, Fig. 203 



340 Frontal section, Fig. 204 



380 Frontal section, Fig. 205 



423 Frontal section, Fig. 206 



572 Frontal section, Fig. 207 



185 Transverse section, Fig. 189 



198 Transverse section, Fig. 191 



249 Transverse section, Fig. 192 



292 Transverse section, Fig. 193 



321 Transverse section, Fig. 194 



jx, Transverse section, Fig. 105 



470 Transverse section, Fig. 196 



513 Transverse section, Fig. 107 



f \,j, Transverse section, Fig. 198 



*K>r making camera lucida drawings, a i-inch objective will be found convenient. 

 is recommended. Compare vhe directions for drawing in Chapter VIII. 



An Abbe camera 



