I02 Laboratory Guide in Zoology 



are removed, the kidneys are to be seen as dark-colored, 

 flattened bodies, fitting closely against the bones of the 

 back, one on each side the spinal column. Find a 

 tubular ureter running from each kidney to the cloaca. 

 XVII. — Nervous System. If the head is cut off and placed 

 in alcohol for a day or two, the brain will b.e hardened 

 so it can more readily be studied. . Remove the upper 

 part of the skull by cutting with strong scissors from 

 the beak over the eyes and around the back of the 

 head, thus exposing the brain. Note these parts of it : 

 the large cerebral hemispheres with the elongated 

 cerebellum immediately behind on the dorsal side ; the 

 two olfactory lobes beneath the front part of the cerebral 

 hemispheres, and the two optic lobes in front of and at 

 the sides of the cerebellum. Make a drawing showing 

 the parts of the brain .as seen from above and another 

 as seen from the side. 



THE CLASSIFICATION OF THE VERTEBRATES 



The highest branch in the animal kingdom is called 

 the Chordata. " It comprises all the Vertebrate Animals 

 (Fishes, Amphibians, Reptiles, Birds, and Mammals), 

 together with the Urochorda, or Ascidians, and the Adelo- 

 chorda, or Balanoglossus, and its aUies. The name Chor- 

 data is derived from one of the most important of the few 

 common features by which the members of this extensive 

 phylum are united together — the possession either in the 

 young condition or throughout life of a structure termed 

 the chorda dorsalis, or notochord. This is a chord of cells, 

 typically .developed from the endoderm, extending along 

 the mid-dorsal line above the enteric tube on the ventral 

 side of the central nervous system. It becomes enclosed 



