TEST QUESTIONS FOR STUDENTS 821 



or epiblastic ? What are (b) wholly endodermic or hypoblastic ? What 

 are (c] wholly mesodermic ? Give an example of a structure (d) partly 

 ectodermic and partly mesodermic in origin. Give an example of a 

 structure (e) partly endodermic and partly mesodermic. 



75. Give a -short account of the skeletal peculiarities in the hind- 

 leg of one of the following : Frog, marine turtle, bird, horse, cow, bat. 

 Contrast the skeleton of the leg chosen with that of man's leg. 



76. State in a couple of lines what is remarkable in the following 

 pieces of skeleton : the coracoid in typical mammals, a bird's rib, 

 a bird's quadrate, a frog's proximal tarsals, the vertebrae of the 

 Bony Pike. 



77. What is a notochord? Describe its condition in the adult 

 Amphioxus, lamprey, dogfish or skate, and mammal. 



78. What is the difference between a "membrane bone" and a 

 " cartilage bone"? 



79. Submit a classification of the Chordate phylum, and indicate 

 the levels at which the following structures began skull, jaws, paired 

 limbs, digits, lungs, fcetal membranes. 



80. Make short notes on the following structures : a snake's vertebra, 

 a bird's columella, a tortoise's plastron, a placoid scale, a frog's 

 sternum. 



81. Make a short note explaining what is peculiar about each of 

 the following : A skate's large intestine, a frog's tympanum, a snake's 

 slough, a bird's syrinx, a mammal's diaphragm. 



82. Make a drawing of the brain of a fish, and explain how it 

 differs from that of a crayfish and from that of a rabbit. 



83. Give a general account of the development of the skull in a 

 dogfish or skate, and explain what complications have occurred in 

 the case of a frog. 



84. In what respects does the circulation in Fishes differ from that 

 in higher Vertebrates ? 



85. Explain the general nature of typical gills in fishes. In what 

 respects do they differ from the gills of a crayfish ? What is peculiar 

 about the gills of a young Elasmobranch, a young Lepidosiren, and 

 a tadpole? 



86. Classify the different kinds of scales on fishes. How do they 

 all differ from the scales of reptiles? 



87. Contrast the important characters of the Dipnoi with the 

 animals immediately above them and immediately below them in the 

 Vertebrate scale. 



88. Give an illustrated account of several different shapes among 

 Fishes, [(i) The typical torpedo-shape, oval in section, becoming 

 cylindrical in section in eels, becoming globular in globe-fish. 

 (2) Flattened from above downwards, as in skate. (3) Flattened 

 from side to side, and swimming on one side, e.g., bony flat-fishes 

 of plaice type. Flattened from side to side and swimming vertically, 

 as in John Dory. (4) Laterally compressed and much elongated, as 

 in oar-fish, gunnel. (5) Peculiar shapes, as in sea-horse.] 



89. Mention several deep differences between a skate and a flounder. 

 [The skate is a gristly fish, the flounder bony, Elasmobranch and 

 Teleostean respectively. The skate is flattened dorso-ventrally, and 



