260 



Observations upon a Species of Gamasus supposed to be 



unrecorded. 



By A. D. Michael, F.L.S., F.Z.S, F.R.M.S., &c. 

 (Read March 26th, 1SS6.J 



Plate XVI. 



I have already mentioned at this Society that for some years 

 past I have been investigating the life-histories of certain 

 parasites of the mole ; and that this inqniry led me last Christ- 

 mas to examine the nests of the moles, in which I discovered 

 several species of Acarina not connected with my original 

 subject, and which I believe to be unrecorded. Amongst these 

 was the fine Gamasus which forms the subject of the present 

 paper. Although I have not been able to find any record of the 

 creature, yet in one stage at least it has certainly been found 

 before, because I have in my cabinet a preparation given me 

 some years since by Mr. Freeman, of this Society, which is 

 marked as coming from the mole, and which is an immature 

 stage of this species. A careful examination of such records as 

 I was acquainted with showed me that this species was so 

 similar to the Gamasus magnus of Kramer,* that I was at first 

 inclined to think that they were either identical, or so similar 

 as to render it undesirable to devote a paper to its description ; 

 for although in groups which have been well worked out, as the 

 Lepidoptera, it would be quite worth recording a single new 

 British species ; yet amongst the less-known families of Acarina 

 I do not usually think it worth devoting a paper to a single new 

 species, unless it has something connected with it that renders 

 it exceptionally deserving of notice. When, however, I came 

 to examine into the structure of this creature, I found that, in 

 spite of the resemblance, it was not Kramer's species, and in 

 the course of the investigation so many points of its anatomy 

 and habits seemed to me interesting and worthy of a record, 



* " Zur Naturgeschichte einiger Gattungen aus der Familie der Gama- 

 siden," ' Arclriv. fiir Naturg.,' xlii, Jahrg. (1876), 1 Bd., p. 91. 



