132 arachnoidea: 



CASE which, though Ave mention last, was first in order of date. This 

 is intermediate between the two others, the legs are not so slight 

 as in Duges's figure and our species, nor so heavy as in the other 

 works. It is near enough to pass for either, but seems to us at 

 least as like Duge's's as Walckenaer's. Now it is to be observed 

 that Hermann, whose original researches after this class of animals 

 were very careful and extended, does not figure the satiny harvest 

 mite in more than one of the above forms. His figure implies 

 that there was only one that he knew. Duges also knew only one 

 form ; but being unable absolutely to reconcile the form he knew 

 with Hermann's figure and description, he, to remove any doubt 

 as to the identity of what he was describing, names it his " Pha- 

 langii." His remarks may be of use in clearing up this obscurity. 

 He says, " Several of the species referred to this genus greatly 

 resemble each other, although differing much in size. We know 

 a gigantic species from the East Indies " (West Africa is its true 

 locality), ''the Tr. tinctorium. With us the satiny Trombidium {i.e. 

 T. holosericeum) reaches a line and half in length. It appears 

 to be rare in the south, at least I have only found it of that large 

 size in our northern departments ; but it must be acknowledged 

 that the harvest mite that I have observed in the south, seems in 

 no respect to differ from it but in size, although indeed 1 might 

 have also been able to refer it to the Tr. triangulare (clerical 

 error for trigonum) of Hermann, which may perhaps not be 

 distinct from the holosericeum. These are uncertainties which 

 the brief descriptions of Hermann cannot dissipate." These 

 two authors were both original observers, and their works re- 

 ferred to are original productions. Those that follow (or at all 

 events the works they wrote) were more literary compilations 

 than original observations, and it has appeared to us possible 

 that, instead of taking their figures anew from authentic specimens, 

 they have merely copied the figures of the authorities who had 

 already treated of the subject. Finding a difference between 

 Hermann's holosericeum and Duges's Phalangii, they have 



