4 NATHAN BANKS. 



baia simplex, 0. monodaciijla, 0. rileyi, 0. amerieana and Eremceus 

 leporus). They are probably from Central America, and I have not 

 seen any of them. Berlese states that O. monodactyla is the same as 

 0. denfntus Berlese. Packard (Cave Memoir) described Oribata 

 alata and Damceus bulbipedata. The desciiptions are incomplete, 

 and the figures not very definite ; the former name is pre-occupied 

 by the common European form, and it appears to be similar to my 

 0. robttsfii. The latter, as stated in the text, is a Be/ba ; it differs 

 from B. )niinda Bks. in having only a few hairs on the abdomen, 

 and in some minor characters of the legs. Dr. Riley, in his notes to 

 Hubbard's " Orange Insects," describes Hermannia(f) trinebidom. 

 This is undoubtedly a larval Oribatid, and I have seen forms quite 

 like it, but I am not sure to what species it belongs. The three 

 species placed by Koch in the genus (Jlavlcep>i ( Arach. aus. Siberien, 

 etc.) are young Oribatids; two species very similar to Dr. Riley's 

 form. The larvae of Oribata pratenms and 0. arborea, which I have 

 collected are of the same shape, but lack the dark patches. 



I have seen no form that would exactly fit European species ; but 

 Nothrus excisus, found on the bark of evergreens, comes very close 

 to the European N. segnis foimd in similar situations. Perhaps on 

 a comparison of specimens, some of our species will prove to be the 

 same as some European forms, particularly those from the northern 

 part of Europe. 



The super-family Oribatoidea is at once divided into two well- 

 marked families : the Oribatida?, in which the cephalothorax is im- 

 movably attached to the abdomen ; and the Hoplophoridse,* in 

 which the cephalothorax is movable. The latter family have the 

 dorsum of the abdomen continued down on the sides and venter, 

 leaving only a small ventral region. The Oribatoidse are readily 

 divided into two sub-families by the presence (Oribatidse) or absence 

 ( NothriuiB) of a tectal plate. Some authors consider these as fami- 

 lies, and equivalent to the Hoplophoridae. Berlese places two other 

 families in this super-family, the Tarsonemida? and the Panopliidiie. 

 Canestrini places the Tarsonemidse next to the Tyroglyphidie. 

 Neither of the families has much resemblance to ordinary Oribatids, 

 and no forms have been recorded from the United States. The 

 Hoplopidse are also sometimes placed close to the Oribatidse ; the 

 species are rare, and no forms are known to me. 



* This name; I suppose, will have to be changed, as Hoplophora is pre-occupied 

 in the Meuibracidpe ; the other genus of the family, Tritia, is, I believe, pre-occu- 

 Xned in the Gasteropods. 



