288 



SYSTEMATIC ZOOLOGY. 



in a direction opposite to that which it followed a moment 

 before. 



The species of Tunicates are numerous , and show great 

 variety of form. A characteristic of many is the power to 

 reproduce by budding, and as a result there are formed 



FIG. 98. Diagram of a Tunicate, b, branchial chamber, perforated by gill- 

 clefts, and connecting at the bottom with the oesophagus, which leads to the 

 globular stomach, and thence by the intestine to the vent, v; h, heart; n, 

 nervous system.; ra, mouth. 



large colonies, the members of which are more or less inti- 

 mately connected with each other. In some cases the 

 animals resulting from budding produce eggs, and these 

 eggs grow into forms unlike their parents, but like those 

 from which the parents were budded. In other words 



