B. Buccal Cavity. 



1. Open mouth, and note — 



(a) The premaxillary, maxillary, and vomerine teeth, the projection of the 



eyeballs, the internal nares and Eustachian tubes. 

 (6) The absence of mandibular teeth, the position, form, and mobility of 

 the tongue, the lingual veins ; the glottis and wide cesophagus, and 

 if a male edible frog the openings into the vocal sacs. 

 ■2. Sketch— 



(a) The roof of the mouth, showing a bristle passing from one of the external 



nostrils into the mouth, and another through the drum of the ear 

 along the Eustachian tube. 



(b) The floor of the mouth, showing the tongue connected to the hyoid 



cartilage, the glottis, and (if present) the openings of the vocal sacs. 



G. Circulatory, Respiratory, and Alimentary Systems. 



1. "Fix the frog on its back by means of pins through the fore and hind limbs, 



cover with water, and divide with scissors the skin along the middle line 

 from the pelvis to the mandible, noting the large subcutaneous lymph 

 spaces. 



2. Pin back the skin, and make a sketch showing — 



(a) The anterior abdominal vein running along the middle line under cover 



of the abdominal walls, to disappear behind the large xiphoid 



cartilage of the sternum. 

 (6) The right and left cutaneous and the brachial veins uniting under the 



pectoral muscles, the lingual and maxillary veins, and the hypoglossal 



nerve. 



(c) The mylohyoid muscle, the sternal and abdominal portions of the 



pectoral muscle, the rectus abdominis, obliquus externus and obliquus 

 internus muscles. 



3. Make an incision along the wall of the abdomen a little to the left of the 



middle line, and observe under the right portion the anterior abdominal 

 vein which originates from the pelvic veins, and after receiving the small 

 cystic, parietal, and cardiac veins, divides to enter the right and left lobes 

 of the liver. 



4. (a) Carefully detach the abdominal vein from the muscles, or make an incision 



a little to the right of the vein, and reflect the abdominal walls ; note the 

 peritoneum lining the body cavity, and covering the viscera. 

 (6) Eemove the sternum and ventral portion of the pectoral girdle, so as to 

 expose the heart and lungs, taking care not to injure the abdominal or 

 cutaneous veins. 



5. Indicate in an outline drawing of the frog — 



(a) The heart lying within the pericardium. 



(6) The lungs, — if collapsed, they should be inflated by introducing a 

 blow-pipe through the glottis. 



(c) The fibres of the rudimentary diaphragm attached to the cesophagus 



and the pericardium. 



(d) The entire right and divided left lobes of the liver, and the gall bladder. 



(e) The anterior abdominal vein entering the lobes of the liver, and its 



cystic and cardiac branches. 

 (/) The exposed portions of stomach, duodenum, small and large intestine, 



the mesentery, and mesenteric veins. 

 (g) The bilobed bladder which, if necessary, may be inflated from the cloaca. 

 {h) If a female, the ovaries, corpora adiposa, and the long convoluted 



oviducts. 



