The species of the tribe Blondeliini of North and Central America and the West Indies (including Trinidad) are grouped into 55 genera. Included is an illustrated key to the genera, a diagnosis of each genus, a list of all generic synonyms, and a taxonomic catalogue of all species recorded from these regions, including their New World synonyms. Type status, type locality, and depository of primary type material is given for each nominal species. One hundred and seventy-seven new generic-level synonyms, 67 new species-level synonyms, and 321 new combinations are proposed. Didyma fuliginipennis Wulp, belonging to the tribe Eryciini, was assigned to the genus Ametadoria (see under lectotype designation of Didyma volucris Wulp). Three new species are described: Ligeria latigena n. sp., from Yukon; Policheta crassisetosa n. sp., from Oregon; and Steleoneura novemmaculata n. sp., from Yukon, Banks Island, and Victoria Island. Lectotypes are designated for 93 nominal species.

In a sense, this book is an expanded version of an earlier work by this author entitled “The Siphonaptera of Canada”, published in 1949. It is extended beyond the political confines of this country and includes treatment of the fauna of Alaska and Greenland, as well as much new distributional information on the fleas of Canada, especially the Canadian north. This latter was made possible by the Northern Insect Survey (1947-1962), mostly directed by the late Dr. T.N. Freeman, which involved the establishment of about 80 field parties in the Arctic and Subarctic Regions of Canada, Alaska and Greenland.A section on flea anatomy in relation to taxonomy is followed by a key to the genera. Then the six families and 15 sub-families, 60 genera and subgenera, and 183 species and subspecies, of fleas are carefully described and illustrated. Under the description of each species is a detailed listing of all specimens available to the author, West to East. This is followed by a host-flea index providing a taxonomic list of all the species of mammals and birds from which fleas have been taken. Distribution maps have been prepared illustrating all the collection records of flea species. Sometimes the known ranges of mammal hosts are included, where there is evidence of a strong host association.

A revision of the hydrophilid subfamily Helophorinae (Coleoptera), containing the single genus Helophorus Fabricius 1775, is presented, including an historical review, a discussion of diagnostic characters and techniques, and an attempt at a phylogenetic reconstruction of the major lineages of the Nearctic Helophorus.Forty-one species are recognized; 9 species and 1 subspecies are described as new.Atractohelophorus Kuweit 1886 is placed in synonymy with Rhopalelophorus Kuwert 1886, and Megahelophorus Kuwert 1886 with Helophorus Fabricius 1775. On the specific level H. ventralis Motschulsky 1860 and H. obsoletesulcatus Motschulsky 1860 are placed in synonymy with H. lineatus Say 1823.A neotype is designated for H. lineatus Say.Lectotypes are designated for H. oblongus LeC., H. fortis LeC., H. regularis Sharp, H. lacustris LeC., and H. alternatus LeC.The genus Helophorus is described and the nomenclatorial and taxpnomic problems surrounding it are discussed in detail. Keys to subgenera and species are provided. Each subgenus is described; each species is described and illustrated, all available bionomic and distributional data are presented, and distributional records are mapped.