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Annals Entomological Society of America [Vol. XV. 



as fixed parasites, the body becomes more flattened and usually 

 elongate. Then in such species as Stigmaeiis floridaniis Banks, 

 which lives in colonies at the bases of imbricated leaves of the 

 pineapple, the body becomes markedly lengthened. Finally, 

 in the genus Phytoptipalpus we find not only a lengthened body, 

 but in the male particularly the body ringed in almost the same 

 way as in the Eriophyidae. (Fig. 4). 



Fig. 4. Phytoptipalpus transitans Ewing. Ventral views of male (smaller 

 individual) and female (larger individual) equally enlarged. 



SUMMARY OF RELATIONSHIPS. 



Thus it is found that in what probably constitutes the three 

 most important groups of morphological structures in the gall 

 mites, that these structures can be homologized with those of 

 the same groups in the Phytoptipalpidas. Further, it is observed 

 that all modifications necessary to give the types of these three 

 important group of characters in the Eriophyidae can be 

 explained, and what is more important, the processes of change 



