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The setae on an abdominal segment are indicated by names 

 which refer to the place of the implantation. 



An identical system has been applied to the thorax in which the 

 same names as far as possible are used. 



Where the homology with the abdomen is not very clear, the 

 changes in the position of the setae have been indicated by 

 other names, because I think that a nomenclature should be a 

 means of describing a thing in a short and clear way, and not 

 an expression of more or less probable hypotheses. 



The shortest method of description certainly is to indicate the 

 whole of the setae on a certain segment as Type I. 



The other ways of arrangement on the abdomen, Type la 

 and lb, can be derived from Type I, by assuming reduction. 



The thoracic segments differ most of all and are called Type II. 

 Very often a reduction of the number of setae has taken place 

 on their dorsal side, but at their oral border there is one seta 

 more than usually occurs on the abdomen. This seta I have 

 called s. dorsolateralh and in so doing I disagree with other 

 writers. By especially studying the setae and the pigmental spots 

 on the pupa and by an accurate comparison of the prothorax 

 with the abdomen, I have come to the conclusion that this seta 

 does not correspond to s, subdorsalis as is generally accepted. 



On the mesothorax and metathorax a pigmental spot is often 

 to be found in the place where we might expect the stigma, if 

 this were exactly situated as on the prothorax. Most investigators 

 have taken this spot to be the rudimentary stigma. It is by 

 studying Boas, that I have come to the conviction that this is 

 not the case, but that this spot agrees with the wing-rudiment. 



A shifting of the stigmata must have taken place and by means 

 of this fact I have tried to explain Type II (Chapter IV). Like 

 Quail I consider the seta in front of the wing-rudiment to be 

 s. prostigmalis (III B.). 



For their bearers the setae may be useful in several ways, but 

 it is difficult to assume, that any correlation could possibly exist 

 between usefulness and arrangement of pattern. The consequence 



