Avian and mammalian kidneys can produce a urine hyperosmotic to the blood by means of a renal countercurrent system. Birds are uricotelic; mammals are ureotelic. It is proposed that the inner medulla present in mammalian, but not in avian kidneys serves specifically to accumulate urea in the inner and outer medulla. Among mammalian kidneys the degree to which urea accumulates in the inner medulla is inversely related to the complexity of the vascular bundles (in the outer medulla) and the cortical urea recycling index. A model is proposed for urea recycling via the vascular bundles. The renal pelvis varies in size among mammals. Its relative size is unrelated to the type of vascular bundles, cortical recycling index, or urea accumulation in the inner medulla. Since urine refluxes into the renal pelvis during rising urine flow only, the function of the pelvis could be that of bringing the more dilute urine into contact with the outer medulla and underlying capillaries, thereby aiding in reducing the urea concentration in outer and inner medulla during rising urine flow. The size of the renal pelvis may be related to the volume of the inner medulla. Other factors may also be involved. This presentation deals with the kidneys of birds and mammals. I shall try to elucidate the intimate relationship between structure and function and suggest how comparative anatomical and physiological studies may lead to new insights into

As was the case with several other genera, the waters of Mount Desert Island contained an unsuspected number of new testudinellids. The anatomy and the trophi are very constant throughout the genus. The salient characters are to be found in the lorica of fully contracted specimens. They are

the local level, the natural and historic resources protected by parks may be integral parts of local communities (Zube 1989). Adjacent residents may value these areas not just as symbols of an American identity, or as recreation places, but as places important to the local character or regional identity. The local connections to national parks can be positive sources of stewardship; however, they may also spur conflict over management decisions about the resource. Thus, national park managers may do well to understand how the places they manage have local significance.

In this paper the description of new species of Notommatidae col-

In the early to mid-201h century, Mvrmica rubra Latreille established in various communities in Maine, mostly along the coast. Since its establishment, the ant has spread both locally via vegetative colony budding and regionally via human commerce to no fewer than 30 Maine communities, including one inland site. Studies were undertaken in the summer of 2002 to address questions of the ants' population structure in its introduced range by testing for intercolony aggression

was tested against its close neighbors, neighbors of lorn within the same infestation, and at two locations within a distinct infestation elsewhere on the island. Aggressive behaviors were quantified, and results suggest a multicolonial population structure, with ants tolerating their close neighbors

68.23°W), a cluster of small islands located in Hancock County. The area is located to the south of Mount Desert Island and at the entrance of Somes Sound, a fjord that splits Mount

In the past and present, the communities of Mount Desert Island in Maine have faced the issue of school consolidation. "- 1948, the four towns of Mount Desert Island each had their own high school and several elementary schools. Despite an extensive survey and community discussion, the vote

ponents were deployed to help visitors travel around Mount Desert Island and in Acadia National Park. Real-time travel information was collected and integrated with Island Ex-plorer buses and disseminated to visitors via an automated annunciator that transmitted an audio message and dis

clusters with samplers at 0.05, 0.10, 0.25, and 0.50 and 1.0m above the soil surface and a 4 × surface creep sampler (0 to 0.02m height by 0.005m wide) was arranged in a circular pattern. The sampling cluster consisted of an array of five samplers each attached to a pivoting wind vane and each mounted at a