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We investigated dispersal patterns of San Joaquin kit foxes (Vulpes macrotis mutica )o n the Naval Petroleum Reserves, California. Of 209 juvenile kit foxes monitored during 1980‐1996, 33% dispersed from their natal territory. Significantly more males (49.4%) than females (23.8%) dispersed, and dispersal peaked in July. Dispersing males tended to be heavier than philopatric males; philopatric females were significantly heavier than dispersing females. Expressed as a percentage of all juveniles monitored, annual dispersal ranged from 0% to 79% for males, 0% to 50% for females, and 0% to 52% for all foxes. Percentage of male dispersal was related weakly to mean annual litter size (r 2 5 0.27), and percentage of female dispersal was weakly and inversely related to annual indices of smallmammal abundance (r 2 5 0.46). Most (65.2%) dispersing juveniles died within #10 days of leaving their natal range. Survival tended to be higher for dispersing males than for philopatric males but was similar between dispersing and philopatric females. Sixty percent of all foxes that survived to breeding age reproduced except among dispersing females, none of which reproduced. Alloparental care did not account for sex-biased dispersal in kit foxes. Auxiliary adults were observed occasionally with mated pairs, but helping behavior was not observed. Dispersal patterns of kit foxes may be a function of innate sex-biased

Thickness of blubber was measured at 48 sites on the bodies of 68 male and 46 female harbor porpoises ( Phocoena phocoena ) from the Bay of Fundy, Canada, and Gulf of Maine and mid-Atlantic coast of the United States. Blubber was thinner over the head than in the thoracic-abdominal region, where thickness varied little around the girth of the animal. Thickness of blubber anterior to the anus ranged from 15 to 25 mm. Posterior to the anus, blubber formed thick dorsal and ventral ridges but was extremely thin laterally. In the thoracic-abdominal region, blubber of calves ( X = 22.9 mm ± 3.6 SD; n = 11) was significantly thicker than that of all other animals, but lactating females had the thinnest blubber (14.5 ± 3.1 mm; n = 7). Immature porpoises of both sexes, mature males, and non-lactating mature females had thicknesses of blubber intermediate between those of calves and lactating females. Thickness of blubber anterior to the anus was correlated negatively with body size, an unusual relationship for a marine mammal. Blubber posterior to the anus was similar among reproductive classes. Blubber of the harbor porpoise appears to be divided into two functional components. The thoracic-abdominal blubber functions primarily as an energy store and insulation, and posterior blubber acts to maintain hydrodynamic shape on the peduncle. Calves and adult porpoises may have different thermoregulatory and energetic strategies, resulting in different adaptations of blubber structure.

The four subspecies of the Pacific species Emballonura semicaudata are considered. Their taxonomic history, distribution, and characters are discussed. On the basis of size and morphology of skull, they form a linear series, semicaudata-palauensis-rotensis-sulcata .

The type of Nycteris vinsoni has been reexamined and the tragus partially reconstituted. It is now evident that the tragus is semilunate rather than pyriform in structure. This character causes N. vinsoni to be transferred from the thebaica group, where I had previously put it, to the macrotis group. I would therefore regard it as a subspecies of Nycteris macrotis .

On March 30, 1946, in the course of making collections of cave fish, Messrs. B. J. Dontzin and E. Ruda obtained a small series of bats from Cueva Sabinos near Valles in the Mexican state of San Luis Potosi. This locality lies in the tropical lowlands of the eastern part of the state (Dalquest, Louisiana State Univ. Studies, Biol. Sci. Ser., 1: 1–229, 1953). This collection is preserved in alcohol and has only recently been identified and catalogued at the American Museum of Natural History. Though consisting of only eleven specimens belonging to four species, it proves to …