24 



SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 56 



Figure /H. A high power drawing of a portion of tiie wall of the oesoph- 

 agus in the region of figure 7A. X IQO. 



Figure 71. A high power drawing of a portion of the wall of the stomach 

 in the region of figure 7c. 



Figure 7J. A high power drawing of a portion of the wall of the duodenum 

 in the region of figure "n. 



Figure 8. An outline drawing, from the ventral aspect, of the enteron of 

 an embryo of 20 cm. length, at aboiu the time of hatching; made from a 

 dissection. X I- 



Lettkring fok .\ll Figures 



(/, hcaihfold of amnion. 



aa, anterior appendage. 



ac. anterior cardinal vein. 



aip, anterior intestinal portal. 



ill, allantois. 



an, anterior nares. 



ao, aorta. 



or, aortic arch. 



an, auricle. 



b, btdbus arteriosus. 

 be, body cavity. 



bd, bile duct. 



bd', opening of bile duct to liver. 

 bd", opening of bile duct to duo- 

 denum. 

 blp, blastopore. 

 /'/', basilar plate. 

 bs, bile-sac. 

 bfj blood vessel. 



c, centrum of vertebra. 

 ca, caudal artery. 



ce, caecum. 



cli. cerebral hemisphere. 



cl, cloaca. 



cm, circular muscle layer. 



en, cranial nerve. 



c(>, posterior choroid plexus. 



cv, cardinal vein. 



d, duodenum. 



dc, ductus Cuvieri. 



(//, diverticulum of stomach. 



e, eye. 



ec, ectoderm. 



cc', thickening of ectoderm. 



e)i, entoderm. 



e7t', endocardium. 



ent, enteron. 



ep. epidermal layer of ectoderm. 



ep', epithelium. 



epi, pineal body. 



(W, embryonic shield. 



/, fronto-nasal process. 



//;, forebrain. 



ff^, foregut. 



gl-^ gill clefts. 



gfi-G^ gill folds. 



gl, glomerulus. 



li, head-fold. 



gs. glottis. 



gs, gizzard. 



lib, hindbrain. 



he, head cavity. 



hg. hindgut. 



ht, heart. 



;', intestine, 



/', stomach. 



il, large intestine. 



in, infundibulum. 



/(', intromittent organ. 



/;', iris. 



it, iter. 



k, kidney. 



/(/, larynx. 



//, liver. 



li)i, longitudinal muscle layer. 



hi, lens. 



Ip, Ip', etc., loops of intestine. 



Ill, lungs. 



!z\, lens vesicle. 



nt, mouth. 



uia, manus. 



nib, midbrain. 



mc, medullary canal. 



me', tip end of medullary canal. 



md., mandibular folds. 



mes, mesoderm. 



mcs', myocardium. 



inf, medullary fold. 



mg, medullary groove. 



mk, Meckel's cartilage. 



