NEW AMERICAN ACARINA. 8 



animal or vegetalile substances, as bones, dead fung-i, decaying sod. 

 A number inhabit moss, esjiecially SpJuKjinini. Some live on the 

 ground, hiding in crevices, under leaves, sticTvS, etc. A few are 

 found on water plants, and one on the rocks between tides. They 

 all move quite slowly, and when disturbed are apt to " play possum" 

 and be overlooked. Most of the species are vegetable feeders or 

 scavengers. In the former role they may be injurious, as 0. j>ra- 

 tensis, which is very common in meadows, and 0. arhorea, which 

 occurs in great numbers on cedai- and peach trees. In the role of 

 scavengers they may often be beneficiaL Packard has stated that 

 Nothru>^ ovivortis sucks the eggs of the canker-worm moth. 



Say, in the Jour. Acad. Nat. Sci. of Phil. vol. ii, 1821, described 

 two species of Oribata, — 0. concentrica and 0. gluhrata, both of 

 which I have identified. The former by the peculiar structure of 

 its abdomen is easily placed in Llodes ; the latter must be an Hop- 

 lophorid, as Say states that the cephalothorax can be deflected on 

 the abdomen, and I have considered it to be the common form which 

 I have collected, and which agrees with the description. Dr. Riley 

 described Hoplophora ardaPi in vi Mo. Kept. 1874 (also in St. Louis 

 Acad. Science). From his figures it appears to be a Tritia, and I 

 think the young of T. glabrata Say. Prof. Packard, in his " Guide 

 to the Study of Insects," described Nothrus ovivoriis ; and Mr. Ash- 

 mead, in "Can. Ent." 1879, described Oribata a^ipidiotii. These 

 two forms are very similar, and perhaps, as Haller suggests, identi- 

 cal ; I have seen nothing that would agree with them. Their char- 

 acters are very peculiar, and if adult ( which is doubtful ) they would 

 certainly be neither Oribata nor Nothrm, nor would they fit in anv 

 genus known to me. 0. aspidiotii certainly seems to be a young 

 form. Fitch, in the 3d N. Y. Kept., describes Oribates 4-pilis ; the 

 description is so short and incomplete it is impossible to definitely 

 identify it. Considering its habits I have seen nothing that would 

 fit it; two species of Oribata are known to me as occurring in num- 

 bers under bark, but both are smooth. It may be mv Scutovertex 

 piloms. Karpelles (Beit. z. Naturgesch. d. Milben, Berlin, 1883) 

 has described two species of ^Yof /;/•».>? from Pennsylvania, N. maHeohis 

 a.nd N. pileiform is. Both are very strange forms (according to the 

 descriptions), and I doubt if they are Oribatids at all, at least not 

 adult ones. I have seen nothing that would agree with them. 



Haller (Beschr. ein. neu. Milben, I Amerikanischer Arten ; Arch, 

 fiir Naturgesch. 1884) describes five species from " Amerika" (Ori- 



TRANS. AM. ENT. SOC. XXII. JANUARY, 1895. 



