86 A. e. OÜDRMANS, NOTES ON ACARI. 



et par suite plus allongées." The nymphs are deprived of 

 course of a genital opening and are configurated otherwise ; 

 they sometimes are so different from the females, that I at 

 first thought them to belong to another species, but fortunately 

 I found in such a case a nymph changing into and still containing 

 a well developed female. 



7. That the eggs have no shell — they are only provided 

 with a delicate membrane — is not a proof of the creature 

 reproducing parthenogenetically, but simply of the living 

 permanently in quills so that a hard shell is superfluous ; 

 moreover they are ovo-viviparous, and as is well known, 

 eggs of ovo-viviparous animals are only provided with a 

 delicate membrane, not with a hard shell. 



8. 1 do not deny the possibily of Syringopidlus reproducing 

 parthenogenetically, for there are more insects which occasionally 

 reproduce parthenogenetically [Jenthredinidae, Vespidae, Apidae, 

 Bombyddae, Psychidae, Talaeporiinae), but I do not see any 

 reason to conclude »que le Syrinfjophilus bipectindtus représente 

 la forme parthénogénésique du Ckeyletus N(">rnen\ for if this 

 were the case, Syrimjopkilus bipectinatus should in no case have 

 males. (Compare my explanations hereabove, p. 80). 



9. The superficial resemblance of Syringophilus bipectinatus 

 and Cheletopsis nörneri did not struck Heller, the discoverer, 

 at all. Heller, who is no acarologist, tells us simply that he 

 found in the quills o f f o w 1 elongate mites which he calls Syrhigo- 

 philiis bipectiiiatns, and in the quills of a peacock another 

 elongate mite which he calls Syringophilus uncinatus. Had 

 Heller been an acarologist, or had he been only a little more 

 acquainted mith the literature on Acari he should immediately 

 have named the mite of the peacock Cheyletus uncinatus. 



10. The elongate form of both Syringophilus and Cheletopsis 

 numeri is simply the result of permanent living in quills, not 

 of any near relationship — though both are Cheletidae. Their 

 legs are not equal in shape, those of the various kinds of 



