ENTOMOLOGY

RELATION OF INSECTS TO THE PARASITIC WORMS 79gordius varius (a common American species), Paragordius tf'icuspidatus,Paraclwrdodes tolusanus, Parachordodes violaccus, Parachordodes pustuloaus,and Chordodea alpeatria.ACANTHOCEPHALA OR THORN-HEADED WORMSThis highly specialized group of parasites, commonly classified in theNemathelminthes, with which it has little in common beyond a superficialresemblance in the general shape of the body, has been but little studied.Most of the known species are parasitic in birds.Macracanthorhynchus hirudinaceua (Pallas, 1781) Travassos, 1916This worm in the adult stage (sometimes called the giant thornheadedworm) is a common parasite of the intestine of the pig and is saidto occur as a parasite of man along the River Volga. Its eggs pass outof the body of the host in the feces. Swallowed by certain insects [larvaeof lJfeiolontha melolontha, Cetonia aurata, Phyllophaga arcuata (Lachnoaterna), and Diloboderus abderua] the eggs hatch, and the larvaedevelop into an intermediate stage, which in turn completes its developmentto maturity when the infested grub is eaten by a pig.Moniliformia moniliformia (Bremser, 1819) Travassos, 1915This parasite in its adult stage (sometimes called the beaded thorllheadedworm) is of common occurrence in the intestine of rats and otherrodents in tropical and subtropical regions, and has been found in manin Italy. The life cycle is similar to that of the giant thorn-headed wormexcept for the difference in hosts. According to Grassi and Calandruccio(1888), Blapa mucronata acts as an intermediate host. According tollagalhaes (1898) and Seurat (1912), the usual intermediate host is acockroach (Periplaneta americana).COl\IPENDlUM OF PARASITES ARRANGED ACCORDING TO INSECT HOSTS 2Ceratophyllus fasciatus BosoHymenolepia diminuta? Hymenolepia nanaA ph aniptera. (Siphonaptera )-fleasCtenocephalus canis Curtis? ACOlnthocheilonema reconditumI The scientific names of the insects have been revised by the editor.