TRAGARDH, TWO MYRTOPODOPIIILOUS ARTENNOPHORINiE. 2.> 



generations are to be fonnd; the nymphse generantes femininse 

 have only got one egg but a large one.^ The last generation, 

 which I have not seen"-^', produces nymphag which are full- 

 grown towards the end of the winter and then develop to 

 adults, which ascend the JuHdse. 



Comparisoii betweeii Neomegistus aiul Paramegistus witli 

 regard to tlieir adaptatioii to tlie myriopodophilous life. 



These adaptations may conveniently be divided in three 

 groups viz. 



1) adaptations for coition 



2) » for feeding pnrposes 



3) » for locomotion. 



1. With regard to coition Neomegistus is by far more 

 highly organized than Paramegistus, which fact most probably 

 is connected with its greater size. In N. the lower jaw of 

 the chela, the button-shaped hypostomatic appendage, the 

 stronger bristles of the ventri-anal shield, fem or a I and the 

 tubercles of the tarsi II and III of the male must be considered 

 to serve the purpose of coition, while in P. only the upper 

 jaw and the legs exhibit special adaptations, but instead of 

 only tarsi II and III also tarsi IV are provided with tubercles. 

 The hypostom of the male in P. is shaped somewhat differently 

 from that of the female but it is difficult to say whether 

 this is of any use for coition or not. 



2. To the second class of adaptations belong the enormously 

 developed laciniae of the mandibles and the large membrana- 

 ceous maxillary plates of both genera as well as, in N., the thin 

 plates along the edges of the maxillary plates. These latter 

 most likely, together with the maxillary lobes, act as a sheet to 

 the mandibles with their fringes and collect as in a pipe the 

 liquid which the mandibles have absorbed with their brushes 

 In P. the lacinise are comparatively smaller and the lateral 

 plates of the maxillary plates are missing. But on the other 

 hand it is worth noticing that in this genus the end of the lower 

 jaw of the mandibles of both sexes is sharply pointed. 



3 The third group of adaptations we find in the shape of 

 the body, the hairs and the legs. 



^ The egg is so large that it seems to indicate that the tritonympha 

 is viviparous. 



^ The last iiympha was caught in the end of June. 



