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in use ; but some anthors object to the name (originally employed for almost all 

 the Orthoptera), apparently with good reason. 



Arixenia is to a certain extent a connecting-link between the earwigs and 

 Hemimertis, not in a phylogenetic sense, but anatomically and morphologically. The 

 eyes, whicli are quite absent in Hemimerua, are much smaller in Arixenia than 

 in the earwigs. The cerci, moreover, agree with those of llemimenm in being 

 hairy, non-segmented, and not modified into callipers, and at the same time 

 resemble iu our larger specimens of Arixenia a little the earwig-callipers, 

 inasmuch as the cerci are somewhat curved towards eacli other. The sensory pits 

 of the antenna are found both iu Heininurm and Arixenia, and the hypopharynx 

 is almost the same in the two insects. On the other hand, the inner lobe of the 

 maxilla bears in Arixenia two apical teeth as in Forjicula, not four as in Hemimeriis. 

 The head is, as in the earwigs, not closely applied to the pronotum. The legs 

 are long and slender, and have a tarsus which recalls Tagalina and Apdeln/us 

 among the earwigs by the proportional length of its segments. The mandible 

 of Arixenia, however, has in its setose inner edge a character which separates the 

 insect very markedly from the earwigs (as far as their mandibles are known) 

 and Hemimerm ; and the alimentary canal, which in Hemimeriis is almost the 

 same as in Forficula auricularia, is very different in Arixenia. 



The similarities between Hemimerus and Arixenia do uot indicate any close 

 relationship, we think. The discussion of that question, however, is better left 

 until the adult Arixenia and the reproductive system of that insect are known. 

 If we may speculate on the derivation of Arixenia, we should say that the insect 

 is a development from some form of earwig like Tagalina, the approximate 

 agreement in the relative lengths of the tarsal segments at least suggesting 

 a connection between the genera. The loss of wings in Arixenia, the reduction 

 of the eyes, and the pecnliar structure of the mandibles are explained by the 

 parasitic life. The hairy cerci, which are found again only in Hemimerus, are 

 ancestral organs, and at first sight appear to speak against Arixenia being a 

 derivation from earwigs with callipers. However, as cerci, though segmented 

 ones, are known to exist iu the larvtie of several genera of earwigs {DipUilijs, 

 Karsckiella, Bormansia), it is ipiite sound to assume that Arixenia developed 

 from a species of earwig which had segmented cerci in its larval stages and callipers 

 in the adult stage, and that, in consequence of the assumption of parasitic habits, 

 the ancestral Arixenia retained the larval cerci through all stages in a shajje 

 intermediate between the long segmented cerci and the smooth callipers. 



1 append a short diagnosis of the family and genas which we have to create 

 for the new species : 



Arixeniidae fam. no v. 



Facies as in apterous earwigs. Head cordiform, not closely applied to the 

 prothorax. Eye present, but reduced (eighty odd facets). Mandible toothed at 

 apex, its inner edge rounded and densely clothed with rigid bristles. Inner lobe 

 of maxilla with two apical teeth. Hypopharynx trilobate. Anteunal segments 

 with two patches of sensory pits from the third onwards. First and second 

 tarsal segments short, third long. (_'erci non-segmented, hairy. Crop of oesophagus 

 large and long; gut with three convolutions. Malpighian tubales arranged in 

 two small and two large bunches. Eleven ganglia in the main chain. Ten 

 spiracles. (Reproductive system not known.) 



