inter pr elation of Insectan & Myriojiodan Structures. 343 



admit, that this view has no foundation in fact. In proof 

 of my contention that the superhnguae (" paraglossae ") 

 of insects are homologous with the paragnaths of Crustacea, 

 I would cite the following facts. 



1. The superhnguae {e.g. of immature Ephenierids) are 

 situated between the mandibles. The paragnaths of many 

 Crustacea occupy exactly the same position. 



2. The superhnguae show no trace of h_mb structure. 

 The paragnaths also show no trace of hmb structure. 



3. The superhnguae function as a secondary underlip 

 (also provided with organs of taste). The paragnaths 

 likewise function as a secondary underhp. 



4. The superhnguae develop as simple protuberances 

 not located in the position typical of the forming mouth- 

 part-hmbs. The paragnaths develop as similar simple 

 protuberances not located in the position typical of the 

 forming mouthpart-hmbs. 



5. The superhnguae are not distinct appendages of a 

 distinct segment. The paragnaths are not distinct 

 appendages of a distinct segment. 



6. The superhnguae have no distinct neuromere, or 

 embryonic ganghon. The paragnaths also have no distinct 

 neuromere, or embryonic ganghon. 



From the foregoing, it should be evident that since the 

 superhnguae and paraglossae occupy the same positions, 

 have a similar development, structure and function, etc., 

 the inevitable conclusion is that the two structures are in 

 every way homologous. Furthermore, the superhnguae 

 cannot be homologised with the first maxillae (maxillulae) 

 because there are already other structures present in the 

 insect's head region, namely the maxillae, which are in 

 every way homologous with the maxillulae, or first maxillae 

 of Crustacea, as is indicated by the following facts. 



1. The maxillulae are situated between the mandibles 

 and second maxillae in Crustacea. The (first) maxillae 

 of insects are situated between the mandibles and the 

 second maxillae forming the labium. 



2. The maxillulae of Crustacea are evidently modified 

 legs. The maxillae of insects are also evidently modified 

 legs. 



3. The maxillulae of Crustacea do not function as a 

 secondary underhp. The maxillae of insects do not 

 function as a secondary underhp. 



