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A New Family of Cavernicolous Millipedes with the Description of a New Genus and Species from Idaho (Diplopoda: Chordeumida: Chordeumidea)
The Chordeumidea is accumulating species names faster than any other group of North American Diplopoda. About one-half its species, 47, have been described since 1950. This recent growth has occurred because the small size, localized populations, and, frequently, cave habitus of these millipeds have obstructed thorough collection in the past. These factors have only recently been overcome by comprehensive collecting. As a result of this rapidgrowth and the many artificial groupings which result from it, much organization of the higher classification remains to be done. Hoffman (1961) emphasizes that co- operation between workers, more thorough descriptions, more accurate illustrations, and revisions are necessary if a proper classification is to be attained.
Described herein is a new cave form unique among the known North American Chordeumidea. Related to Cleidogonidae, Conotylidae, and Bactropidae, it is distinguished from these families by having the ninth legs reduced and unsegmented. This species represents the type of a new family, which we name after the state in which it was collected
Effectiveness of a Rigid Grate for Excluding Pacific Halibut, Hippoglossus stenolepis, From Groundfish Trawl Catches
A rigid grate was installed in a groundfish trawl to test its effectiveness in excluding Pacific halibut, Hippoglossus stenolepis, from commercial flatfish catches in the Gulf of Alaska. The grate was located ahead of the trawl codend to direct halibut toward an escape opening while allowing target species to pass through toward the codend. In an experimental fishery, the escape rate of halibut was estimated at 94%, while 72% of the Dover sole, Microstomas pacificus, 67% of the rex sole, Glyptocephalus zachirus, and 79% of the flathead sole, Hippoglossoides elassodon, were retained
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