108 A. D. MICHAEL ON TWO SPECIES OF ACAIIINA. 



not belong to the family I was in search of, and, indeed, at first, I 

 had doubts whether it was one of the Acarina at all ; I, however, 

 soon felt that the resemblances to the Phalangidce and the Pseudo- 

 Scorpiones were only superficial, while those to the Acarina were in 

 essential characteristics ; but when I came to decide upon what 

 family it belonged to, it was a very different matter. There seemed 

 such serious objections to including it in any known family, that, 

 being busy with the Oribatidce, I allowed the matter to stand over, 

 hoping to find more specimens and investigate further. In this I 

 was tolerably successful, for during the season of 1879 I found a 

 number of specimens, both in the perfect and nymphal stages ; but 

 in the meantime a notice of the creature from the pen of Dr. 

 Kramer had appeared in the first number of the " Archiv fur 

 Naturgeschichte " for 1879. Dr. Kramer does not say when he 

 found it, but it is probable that it was before I did ; he has given it 

 the name above quoted. Subsequently to my finding it, Mr. 

 George, of Kirton Lindsey, found some specimens ; and, not being 

 aware of its previous capture, was as much puzzled as myself. 



I cannot say that I am any further advanced than I was in 1878 

 in the question of what family it belongs to, and Dr. Kramer has 

 evidently felt the same difficulty, but he escapes from it in a way 

 which I confess did not strike me ; he creates a new genus for it, 

 says that it is very difficult to classify, and that it is not one of the 

 Orihatidce — an assertion which he is quite safe in making — and 

 there he leaves it. I must, I fear, in the main follow his example ; 

 but I will briefly point out the reasons why it is difficult to include 

 it in any established family. 



Analogies. 



Firstly, as to those creatures which have a certain resemblance 

 but do not belong to the Acarina, From the Phalangidoi it is 

 divided by its unsegmented abdomen, tarsus of one joint, and the 

 position of the genital organs. From the Scorpionid(B it is divided 

 by the absence of constriction between cephalothorax and abdomen, 

 and by the latter not being segmented, notwithstanding the singular 

 resemblance of the mandibles of this species to the chelicera} of 

 Obisium, &c. 



Among the Acarina, the hard exo-skeleton covering the whole 



