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Background: Triatoma protracta is a triatomine found naturally throughout many regions of California and has been shown to invade human dwellings and bite residents. A man living in Mendocino County, California, reported developing anaphylactic reactions due to the bite of an “unusual bug”, which he had found in his home for several years. Methods: We conducted environmental, entomological, and clinical investigations to examine the risk for kissing bug invasion, presence of Trypanosoma cruzi, and concerns for Chagas disease at this human dwelling with triatomine invasion. Results: Home assessment revealed several risk factors for triatomine invasion, which includes pack rat infestation, above-ground wooden plank floor without a concrete foundation, canine living in the home, and lack of residual insecticide use. Triatomines were all identified as Triatoma protracta. Midgut molecular analysis of the collected triatomines revealed the detection of T. cruzi discrete typing unit I among one of the kissing bugs. Blood meal PCR-based analysis showed these triatomines had bitten humans, canine and unidentified snake species. The patient was tested for chronic Chagas disease utilizing rapid diagnostic testing and laboratory serological testing, and all were negative. Conclusions: Triatoma protracta is known to invade human dwellings in the western portions of the United States. This is the first report of T. cruzi-infected triatomines invading homes in Mendocino County, California. Triatoma protracta is a known vector responsible for autochthonous Chagas disease within the United States, and their bites can also trigger serious systemic allergic reactions, such as anaphylaxis.

Twenty-nine radiocarbon-dated pack rat middens document woodland communities in the deserts of the southwestern United States less than 10,000 years ago. A synchronous change from woodland to desert or grassland occurred about 8000 years ago in the Chihuahuan, Sonoran, and Mohave deserts. A shift of the Aleutian low and the winter storm track to the north, which resulted in drastically reduced winter precipitation in these areas, is inferred. The shift to nonpluvial climates in the Southwest lagged behind the beginning of nonglacial climates in the North because the melting continental glaciers contined to affect general circulation patterns.

Major taphonomic influences upon stone artefacts have been usually regarded as physical - fire, water, earth and air. Treadage and scuffage by people or other biological agents may be important but active displacement of stone artefacts by animals has received little attention. Cane (1982) described the use of artefacts as gastroliths by the Australian bustard and Horton (1978) has raised the possibility that seals and some sea birds may move artefacts or introduce foreign stone to deposits of bone. In North America the pack rat Neotoma carries stone objects in its cheek pouches and places them in heaps at its nests (Walker 1964) and, in Australia, the pebble-mound mouse, Pseudomys chapmani , marks past and current burrows with 'piles of small rounded stones' (Kitchener l983:416). There is the possibility that both these species might transport artefacts. We report here that the 'odds and ends' collected by the great bower bird, Chlamydera nuchalis , may include large numbers of stone artefacts. This behaviour by the birds could sometimes produce small-scale, local increases in the density of artefacts or bias the size and colour classes found in surface collections of artefacts. Solomon et al . (in press) have made similar suggestions regarding assemblages of bone found at bowers of the great bower bird. The work reported here was at Black Rock, northeast Queensland in July 1985.

The extinct Harrington's mountain goat (Oreamnos harringtoni Stock) is predominantly known from dry cave localities in the Grand Canyon, Arizona, in addition to two sites in the Great Basin, Nevada, and from San Josecito Cave, Nuevo Leon, Mexico. A dry shelter in Natural Bridges National Monument, on the central Colorado Plateau, southeastern Utah, preserves numerous remains of the extinct mountain goat in addition to pack rat middens. Remains from a 100-cm stratigraphic profile indicate that O. harringtoni lived on the plateau >39,800 yr B.P., the oldest directly dated find of extinct mountain goat. Plant macrofossils indicate that Engelmann's spruce (Picea engelmannii), limber pine (Pinus flexilis), rose (Rosa cf. woodsii), and Douglas fir (Pseudotsuga menziesii) grew during the late Pleistocene where a riparian and a pinyon-juniper (Pinus edulis-Juniperus osteosperma) community now predominates; Douglas fir are found only in mesic, protected, north-facing areas. Limber pine, Douglas fir, bark, and grasses were the major dietary components in the dung. A springtime diet of birch (Betula) is determined from pollen clumps in dung pellets.

The distribution ofUloborus diversus webs around pack rat nests on the desert near Cave Creek, Arizona, differences between webs there and in nearby residential Phoenix, and differences between the webs of large and small individuals indicate that these spiders select web sites and designs to minimize web damage by wind. The frequency of web construction decreased when spiders in captivity were exposed to wind or to relatively bright (5 Lamberts) nights. Observations of web sites on the desert revealed high rates of web-turnover and substantial frequencies of movements of spiders from one site to another. Much lower rates of web-turnover and spider movement occurred in less windy situations in the laboratory, and in suburban Phoenix. Partial web replacement and the extension of web construction over two nights are apparently methods used to improve catching ability of sheltered (longer lived) webs by extending their surface and/or tightening their mesh.

Although the importance of animals in soil formation is recognized, and is usually briefly mentioned in most soil text books under the title of "biological forces," little data has been presented to show just how important these forces might be. The literature contains a wealth of material concerning the activities of soil bacteria, fungi, protozoa, and to a much less degree, the invertebrate fauna of the soil. Little work, however, has been done concerning the constructive activities of various larger animals. The relation of earth worms to soil fertility was first discussed by Darwin (I). The invertebrate fauna of the soil (Nematoda, Annelida, Myriapoda, Insecta, etc.) are discussed by Russell (4). Shaler (5) has given animals an important place in the soil formation, considering ants as playing a more active part than earthworms, and suggesting that vertebrates, especially mammals, have as great an effect as the lower forms of animal life. The activities of higher animals in this connection have been emphasized by Taylor and McGinnies (8), and by Taylor (7), who suggested that Shaw's formula for the expression of the principal factors controlling the trend of soil formation and development be modified to include the factor of animal life. The purpose of this paper is to show quantitatively, from the results of chemical analyses, the effects produced in the soil by some of these higher animals. Two rodents, which are quite common in southern Arizona, the so-called banner-tailed kangaroo rat (Diplodomys spectabilis spectabilis) and the white throated wood rat ("pack" or "trade" rat) (Neotoma albigula albigula) will be considered. The life history of the former has been described in detail by Vorhies and Taylor (9), and a good description of the latter is given by Nelson (3). The field studies were made on the Santa Rita Range Reserve, a grazing substation of the Southwestern Forest and Range Experiment Station, United States Forest Service. This substation is located at the northwest base of the Santa Rita mountains, approximately 35 miles south of Tucson.

A marking experiment with Uta stansburiana stelnegeri was conducted during the summer and fall of 1960 in a sandy mesquite area in western Texas; additional data on some aspects of the study were obtained in the summer of 1961. Many lizards were captured 5 or more times so that fairly reliable estimates of home range size were obtained. The home range averages .06 acre in adult males, .02 in adult females and .01 in juveniles. This is smaller than averages reported for other North American lizards. In the study area immigration and emigration were negligible and estimates of population density showed 18.4 adults and 50 or more juveniles per acre. Most juvenile mortality occurs after hatching. Most of the adult lizards are monogamous. The home ranges of males in the breeding season show little or no overlap suggesting that the males display territoriality throughout the home range. The choice of home range and the ultimate size limit of the population seem to be determined by the position and number of pack rat nests in a given area. Distribution and abundance of vegetation and texture of the substratum are of secondary importance. The pack rat nests are importanlt to the lizards as shelters and retreats. Juveniles probably establish home ranges within or near those of the parent, a fact made possible by the death of the adults near the end of the reproductive season. The importance of specific plant species in the ecology of these lizards and possible predators, competitors, and other associates are discussed.

Little has been recorded on the reproduction and growth of young Neotoma f. floridana, although accounts of the subspecies of floridana and related species are available (English, 1923; Warren, 1926; Gander, 1929; Svihla and Svihla, 1933; Donat, 1933; Wood, 1935; Poole, 1936, 1940; Vestal, 1938; Vorhies and Taylor, 1940; Richardson, 1943; Linsdale and Tevis, 1951). The present report is based on captive Florida wood rats collected in the region of Sarasota, Florida by William Hegener and shipped to me in the early spring of 1950. These animals were taken in swamps three miles east of Venice, Sarasota County. Mr. Hegener believes that wood rats do not occur south of this locality. When shipping the specimens, Hegener wrote in reference to the nest site and young (in litt. March 21, 1950): "I was trapping for cotton rats (eight miles east of Tampa, Florida on March 21, 1950) in the dead, high sunflower stalks which surround the dried-up part of this swamp. The purpose was to get cotton rats with infection of microfilariae. In the middle of the swamp are willows and high ground, which even in the rainy season is a little above water. Under one large willow I found a one and a halffoot nest, made of dry sticks up to an inch in diameter, and dry leaves. The sticks and leaves reached in height about 3 inches over a low-slung thick branch of the willow bush. While I was wondering about this peculiarly built and located 'alligator nest' I thought I saw a flash of a fast moving animal into this rubbish heap. Upon investigation I observed two rather large entrance holes into the rubbish pile.... We returned to the nest with nets.... We took the pile carefully apart until we hit a populous colony of large bull ants.... When we had the entire pile levelled to the ground we decided that I had imagined things, since we had carefully watched that no animal would escape unnoticed.... I looked under the thick branch of the willow tree, after clearing off the rubbish pile, now about a foot above the ground. Underneath it I found a hole, going into the partly dried upper branch. A whitish tail end stuck out of it. I poked in the hole with a stick and removed a female pack rat with one baby hanging on its teat.... The pack rat has from two to three, sometimes four, which the females carry for about two months." This is the information we have on nesting of the Florida wood rat at its southern limits! I have searched the 'glade country for Neotoma sign but have not found them south of the limits Hegener indicates. Probably these rats occur in the recesses of the swamps farther south; others may find them in time. (A paper on Neotoma f. floridana by Pearson (1952) appeared after the present report had been submitted for publication. The data on growth of the young are essentially the same. Pearson indicates gestation may be 33 to 39 days. Other data closely agree with the present study.) The animals in this study were kept in sizeable hardware cloth cages in an outdoor animal shed. The shed was shaded by a canopy of leaves on trees that re180 Vol. 34, No. 2