somewhat rounded above with the opening in the lower projection. A few mites were crawling about on the leaf surface. They are orange in color. Eriophyes padi Nalepa Anz. Ak. Wien., XXVI, 1889, p. 162 This mite causes the numerous elongate pocket galls on Prunus spp. in Europe and North America. I have collected it often on Prunus serotina in southern Ohio. apex and a strongly constricted neck. trichomes arise from the inner walls. usual case with these structures. white to pale orange in color. They usually have a pointed Eriophyes phloeocoptes Nalepa S. B. Ak. Wien., XCI, t. 6, 1890, p. 54 This is the common "Plum-leaf gall mite" of Europe and North America. The mites cause a marked discoloration of the leaves, which become brownish and rather wrinkled. The mites usually work on the lower surface. Their attack frequently results in premature defoliation and an accompanying loss of fruit. The control recommended for the next species is also effective against this one. It is fairly common in Ohio. Eriophyes pyri Pagenstecher This is the common "blister mite" of pear and apple and seems to be cosmopolitan in its distribution. As the leaves unfold in the spring they may show brownish blotches. At first they are most conspicuous on the upper surface but as the season advances the tissue dies and becomes brown on both upper and lower surfaces. These usually mark a very flat blister-like structure opening on the lower surface. In this the mites are active but occasionally they are found on the outside. Newly formed galls are usually quite succulent. Occasionally they may attack the fruit. The species is known from close relatives of the pear and apple also. Partial defoliation with consequent decrease in crop yield follows attack by this mite. The most effective control yet devised is a lime-sulphur spray applied at the time the buds are swelling in the spring, but after they are open it is too late. Summer spray with either lime-sulphur or oil emulsions are not effective. Eriophyes quadripes Shimer Trans. Amer. Ent. Soc., II, 1869, p. 319 This species causes the small red or green pouch galls on soft maples. They are quite irregular in shape. No trichomes appear except at the neck. The inner surface is ridged by irregular, fleshy protuberances. The size varies considerably. No galls have been found containing more than one adult but this is probably to be explained by the recentness of the infestation. Little injury results to the host, nor have I seen any degree of defoliation from the attack of this mite. All sections of Ohio are infested. Eriophyes salicinus Nalepa Denkschr. Akad. Wiss. Wien, 1899, LXVIII, t. 5, p. 213 This species causes capsule galls on Salix sp. in Europe and North America. The galls are small, red or green in color, irregular in shape, and filled with fine trichomes. Scarcely a specimen of S. nigra in southern Ohio is free of this species. Eriophyes tetanothrix var. laevis Nalepa Denkschr. Akad. Wiss. Wien. LXVIII, 1899, p. 215 This species causes pocket galls on Salix sp. in Europe and North America. They are rather composite structures with elongate, irregular openings in the lower surface. Fleshy trichomes line the galls. It is common on S. nigra about Chillicothe. Eriophyes thujae Garman App. 12th Illinois Rpt., 1883, p. 138 This species occurs on various horticultural varieties of Thuja occidentalis. It may be synonymous with a European species. The only evidence of its presence is a yellowish discoloration of the terminal growth which may terminate in death. It is widely distributed in North America. Summer strength lime-sulphur is partially effective in controlling this mite. Eriophyes tiliae Nalepa S. B. Ak. Wien., XCI, t. 2, 1890, p. 46 Sears reports E. abnormis Garman from Tilia americana at Cedar Point. I believe that this name is synonymous with E. tiliae Nal. It causes small pouch galls on the upper surface of the above host and on Tilia spp. in Europe. Eriophyes tristriatus Nalepa Anz. Ak. Wien, XXVI, 1889, p. 162 This species causes pouch galls on Juglans sp. in Europe. I have taken what appears to be this species on Juglans nigra in southern Ohio. The mites were not associated with galls altho typical galls were present on the tree. Eriophyes ulmicola Nalepa Anz. Akad. Wiss. Wien., 10, 1909, p. 117 This mite causes the pouch galls so common on Ulmus americana and U. fulva in North America. It is common in Ohio. The galls are dark green in color, have a pointed apex, and a constricted neck. They are densely packed with fine trichomes. The opening is on the lower surface. Mites vary from milky white to orange in color. Subfamily Phyllocoptinae These mites have at least twice as many ventral semi-annulations as dorsal ones and the cephalothorax frequently projects beyond the rostrum. I have five species in two genera from Ohio. The genus Phyllocoptes has the dorsum evenly curved and the end piece of the abdomen indistinctly separated from the rest. One species, P. schlechtendali is of considerable importance from its attack on pear. Phyllocoptes aceris Nalepa N. Acta Ac. Leop., LXI, t. 4, 1894, p. 313 This species causes the common nail-like galls on Acer spp. in Europe and North America. It is common on Acer saccharum thruout southern Ohio. The galls are sharply pointed and open on the lower surface. Within there are longitudinal ridges frequently extending a short distance thru the opening. The mites are orange in color. Phyllocoptes magnirostris Nalepa Anz. Ak. Wien., XXIX, 1892, p. 128 This species causes small pocket galls on Salix fragilis in Europe and North America. The galls are red or green thruout. The neck is constricted slightly and small fleshy trichomes fill the interior. It is a common species in southern Ohio. Phyllocoptes mastigophorus Nalepa N. Acta Ac. Leop., LXI, t. 3, 1894, p. 308 This species occurs on Ulmus spp. in Europe and North America. It does not seem to form galls. I have taken it abundantly from beneath the webs of Tetranychus telarius on Ulmus ameri cana. It can make its way thru and over the webs of the latter without any apparent difficulty. It may be responsible for some of the discoloration of Ulmus spp. Phyllocoptes toxicophagus Ewing Proc. Ia. Acad. Sci., XXIV, 1917, p. 324 This species causes the numerous irregular green or red pouch galls on the leaves of Toxicophagus toxicodendron or poison ivy. The gall cavity is much branched and filled with trichomes. There is but a slight constriction on the lower surface at the gall openings and, since the trichomes often do not choke these, the activities of the mites may be easily studied. The mites are very common. Their distribution is general with the host. In the genus Anthocoptes the terminal piece of the abdomen is plainly separated from the rest of the body. Anthocoptes platynotsus Nalepa Anz. Ak. Wien. XXIX, 1892, p. 191 This species is common on Cornus spp. in Europe and North America. I have taken it on Cornus florida in southern Ohio. It causes no deformities of the leaves. The orange colored mites were taken on the lower side of the leaves in large numbers. CONCLUSIONS In presenting this introductory study of the mite fauna of Ohio I have but hoped to begin a work that I trust others will aid me in continuing. There are few acarologists in our country and but few more abroad. The subject offers a very broad field for taxonomic and biological research. The student in search of problems will find acarology replete with them. Every species is deserving of painstaking investigation of its biology and relationships. The technique is but poorly developed and each student should make an effort to improve upon it that this science may become more certain in the results which are achieved. In an effort to record all the species actually known to occur within the State, I can present 127 species. Some of these are new to our national fauna and many are new for the State altho their presence might have been suspected. A more accurate knowledge of the distribution of these species is therefore available. Of these species, 28 are of direct economic importance to us because of their actual or potential capacity to cause losses to human industries. I have appended to the discussion of each species of this nature the most effective practical control thus far known and have attempted to so index this volume that such information may be readily accessible to those interested in these data. The reader has probably noticed the complete lack of keys. As in any work of this character these might have been constructed, but I have felt that since I have by no means a complete list of our Acarina and that many genera contain but one, or at most a very few species as at present known it would be of little value and would but lead to confusion when later material is discovered. I have endeavored to present the major taxonomic characters so as to enable the student to ascertain whether the species in hand is the one here recorded. In the course of my studies I have collected upwards of fifty species that appear to be new and many more that lack of time has prevented me from placing specifically. Other tasks permitting, I propose to continue the study of our acarid fauna and from time to time present such contributions as these studies may make possible. |