ENTOMOLOGY

RELATION OF INSECTS TO THE PARASITIC WORMS 77Setaria labiato-papiUosa (Alessandrini, 1838) Railliet and Henry, 1911The adults of this nematode are common parasites in the peritonealcavity of cattle in various parts of the world including the United States.The larvae enter the blood stream, and Noe (1903) identifies certainlarval nematodes found in Stomo:cys calcitrans as belonging to thisspecies. That this fly actually serves as the intermediate host, however,remains to be proved.The possibility is not excluded that Noe mistook Habronema larvmfor the larvIE of S. labiato-papillosa.OncocercaAbout twelve species of this genius have been described. Oncocerca'Vol'V'lllus in the adult stage occurs, in nodular tumors beneath theskin of man in Africa. Oncocerca caecutitmB is found in subcutaneousnodules on the head among natives living at a certain altitude on thewest coast of Guatemala and is the cause of so-called "Coast erysipelas."O. gibsoni causes worm nodules in the brisket and other locations incattle in Australia. Two species occur in cattle in the United States:one undetermined species is found in relation with the ligaments of thelegs and neck, the other (0. lienalis) is found in the gastrosplenic ligament.Oncocerca larvae have not been found in the blood stI:eam butmay be recovered from the lymph spaces in the neighborhood of the adultworms. The intermediate hosts of these nematodes are unknown but bitinginsects have been suspected. The results of experiments have been negative.Brumpt (1903) has suggested the possibility that Glossina palpalisacts as intermediate host of O. 'Volvulus.Robles (1919) suggests that two species of Simulium (close to S.dinelli and S. samboni) may be involved as vectors of O. caecutiens inview of the fact that these flies are most numerous in the places wherethe largest number of cases of Oncocerca occur. Furthermore thesespecies of flies are absent in lower altitudes corresponding with the absenceof Oncocerca.3. Other N ematodcaDifferent investigators have recorded the occurrence of larval nematodesof unknown species in various insects. tJsuaUw these have beenvery poorly described and it is questionable in many cases whetherif found again they could be recognized as the same forms. Some ofthem may be the larval forms of nematodes whose adults are alreadyknown as parasites of higher animals. Among such larvae of uncertainidentity may be mentioned Filaria geotrupis In the abdominal cavity