cyclamen is frequently attacked it has given to the mite the common name of "cyclamen mite." "Pallid mite" is also used by some authors. The eggs are usually laid during the night in the vein angles on the lower side of the leaves. They hatch in from three to seven days at normal temperatures. There seems to be but one larval stage, lasting from 3 to 6 days. About half of this time is spent in a quiescent state. Following this the adult appears and oviposition begins in a few days. A single female may lay 16 or more eggs. Parthenogenesis has been observed and may continue thru several generations. In greenhouses the cycle repeats itself thruout the year. Mature plants that are heavily infested can hardly ever be saved. Where infestations have occurred during previous years florists should begin early in the season to apply "Black Leaf 40" at the rate of 1 part to 1,000 parts of water, adding soap at the rate of 3 pounds to 100 gallons. Many other remedies have been used but none are at present better and few cheaper than the above. Family Pediculoididae This family differs markedly from the preceding. The female has the hind legs terminating in claws and caroncles and when gravid she assumes enormous proportions. The species are quite prolific. There are but a few species in several genera. Several are known from North America. They are all quite minute. Pediculoides graminum Reuter and P. ventricosus Newport are quite common in many parts of the world, especially in grain growing regions. Their biology as well as that of several others is well known. A number of species are known to attack plants and scale insects, as do the Tarsonemidae. Some seem to transmit disease as P. graminum and its close relation with bud-rot of carnation. P. ventricosus and others are frequently found associated with various dipterous, hymenopterous, coleopterous, and other insects upon which the mites are often parasitic. Where this habit centers about an injurious insect the mite can be considered distinctly beneficial. From this state the mite often assumes a marked economic aspect from certain injuries which they may cause. P. ventricosus has long been known from standing and cut grain where its parasitism upon the joint worm and the grain moth larvae had brought it into good standing as a beneficial species. ac T Grain straw was frequently used for filling mattresses and in packing of pottery and if not thoroly cleaned it often carried numerous mites into these several industries. Harvesters in the field, workers in straw mattress factories, those sleeping on straw mattresses, workers in pottery packing rooms, and others coming in contact with straw often experienced very severe outbreaks of an irritating dermatitis on all parts of the body. After some research the beneficial parasite was found to have the faculty of becoming extremely noxious to man. P. graminum also possesses this habit. Pediculoides ventricosus Newport Trans. Linn. Soc., XXI, 1853, p. 95 These mites are quite minute and have the characters of the family. The eggs are not deposited but carried within the abdomen of the female where in time they will hatch. Development through the several metamorphoses to maturity occurs before the mite issues from the abdomen of its mother. They may even issue after the death of the latter providing development has proceded far enough. Males are seldom taken and parthenogenesis is common. The species is common in Ohio and thruout North America altho it does not seem to occur as frequently as formerly. It is my opinion that many cases of so-called "chiggers" are attributable to this species and not to Trombidiid larvae. Suborder ATRACHEATA Included here are a large number of mites of very diverse habits. The adults are always octopod and the legs are supported by chitinous ridges or epimera; there are no tracheae present; the small, usually three-segmented palpi are more or less fused to the base of the rostrum. Section BRACHYPODA But one family of one genus is included in this division. The three segmented legs are quite rudimentary and the body vermiform. Transverse annulation give the appearance of segmentation. These mites are known to occur in the hair follicles and sebaceous glands of some vertebrates thus giving the name of "follicle mites." Family Demodicidae This family and its one genus Demodex have the above characters. Several domestic animals and man are hosts to the several species. Many points of the biology are still uncertain. The very minute, white eggs are spindle shaped and deposited in the pustule inhabited by the parent. A small white hexapod, apparently apod, larva hatches. The legs appear as rudimentary tubercles. After a short time the larva molts and an octopod nymph appears. It greatly resembles the adult. It undergoes two more molts before maturing. Adults measure about .4 mm long by .04 mm wide. They and the nymphs are free to move about over the body from follicle to follicle and thus distribute the infestation. Living only on warm blooded animals there may be a number of generations each year. Most domestic quadrupeds and some rodents are subject to attack. Poor bodily sanitation favors an infestation. On man the angles of the nose and similar places often slighted in bathing serve as places of establishment for the mites. Their attack on all hosts results in a small whitish pustule at the base of the hair or including the entire sweat gland. These often appear as "blackheads" and among certain classes of people the latter may be caused by mites, altho "blackheads" usually have a different origin. Various workers have held Demodex capable of transmitting certain human diseases such as leprosy, cancer, and certain forms of eczema. Altho there is a possibility of this occurring, there is, to my knowledge, no proof of its certainty. Cleanliness is the best safeguard against an infestation. Sulphur ointments for man, and cattle dips for livestock are the usual treatments. I have records of two species from Ohio but feel that a thoro canvas of our clinics would also reveal Demodex folliculorum Simon, the common follicle mite of man, since this species has a cosmopolitan distribution. Those of other domestic animals may also occur in the State. Demodex canis Leydig Ann. Nat. Hist., XIII, 1844, p. 75 This is a cosmopolitan species on the dog. I have several records from about Chillicothe. It very likely is generally distributed thruout the United States. Demodex bovis Stiles Can. Ent. XXIV, 1892, p. 286 I have several records of this species from Ohio, and it has been reported from a number of places in North America and Europe. Section EPIMERATA In these mites the body is short and stout and the legs are more than three segmented. It includes six families which usually comprise the superfamily Sarcoptoidea. Family Tyroglyphidae This family has the integument usually smooth; the tarsi without stalked suckers; and the adults never parasitic. It does not comprise many species but some of these are of considerable economic importance. Michael has given us a beautiful monograph of the British forms. Nearly all the species are oviparous, scattering the rather large eggs about in whatever material the mite happens to be in. Upon hatching milky white hexapod larvae appear. These molt, shortly to appear as octopod nymphs which resemble the adults. Hence forth the mites may, and in many species do, pursue one of two courses to maturity. In one of these there is nothing unusual since, passing thru several molts, an adult appears. All stages in this course are active. The other course brings us to a hypopal stage or Hypopus which is another of those interesting adaptations often found in biology. It has been the cause of many new descriptions and consequent taxonomic confusion, many false impressions of beneficial parasitism, etc., but is now known to be but a quiescent stage supplanting the normal second nymphal ecdysis. In this stage the mite bears rudimentary legs poorly adapted for walking and nonfunctional mouthparts. It clings to its insect carrier by means of a group of suckers on the posterior ventral surface. This separates them from the nymphal Uropodidae which are attached by a pedicel. So many of these hypopi cling to an insect at times that the latter may die thru its efforts to move about. The causes bringing about the hypopus are not known. It does serve as a means of tiding the species past a dry season or failure of food but may occur when these factors are normal. It also serves as a means of distribution. All individuals of species having a hypopal stage pass thru it before maturing. Some species enter a similar stage but do not attach to insects. A nymph usually appears from the hypopus after which maturity is reached. Some species show a marked sexual dimorphism. The male is the smaller. This life cycle is that passed thru by nearly all the species in the family except for variations determined by food supply and climatic factors. Where the food material consists of stored food products, as it often does, there may be a number of generations a year, while out-of-doors there are fewer. Of the fifteen or more genera included in the family, five are now known to have representatives in Ohio. The genus Glyciphagus has the mandibles chelate; the palpi normal and without prominent bristles; the dorsal integument more or less granular, which character separates it from allied genera; the tarsal claws very weak; and some of the body hairs slightly feathered. These mites are commonly called "sugar mites" from their frequent occurrence in this material, altho they are often found in other grocery goods, stored grains and seeds, animal products, etc. Those finding employment in buildings infested with these mites often suffer from an irritation known as "grocer's itch" due to these mites wandering about on the body, altho they are never parasitic there. Species of this genus and others allied to it have been reported from the intestinal tract and its contents, but this seems quite doubtful. Glyciphagus domesticus deGeer Adults are a dirty white to pale brown color and .4 mm long. The abdomen and cephalothorax are closely fused; the dorsal hairs are finely feathered and of but one kind; there is no conspicuous hair on the 4th segment of legs I and II but two smaller hairs are present on this joint. The species is recorded from stored grain in several Ohio localities. It is generally distributed in the United States and Europe and reported from a wide variety of dried animal and vegetable products. Glyciphagus robustus Banks Tech. Bul. 13, U. S. D. A. Bur. Ent., 1906, p. 13 This is a smaller species than the preceding being but .25 mm long. It has a long hair on the 4th segment of legs I and II. The type material was collected in seeds at Leetonia, Ohio. It is not as common as the preceding species. The genus Histiostoma contains those mites with a smooth but slightly undulating dorsum; tarsal claws distinct; no prominent feathers or long hairs on the body; the mandibles not chelate; and the distal palpal joint enlarged and bearing two divergent bristles, which character is quite distinctive of the genus. The species are apparently scavengers in a wide range of decaying animal and |