ENTOMOLOGY

RELATION OF INSECTS TO THE PARASITIC WORMS 75the intennediate host of Acanthocheilonema perstans. Wellman (1907)­has reported that the larvae of this parasite are taken up by Ornithodorosmoubata and according to his statements develop very slowly in thistick, advanced stages not being found until more than two months afterinfection of the tick. The suggestion made by Feldmann (1905), influencedby Bastian (1904), that the larvae of A. perstans may pass outof the body of the tick with its eggs into bananas and afterwards beingswallowed with this fruit by human beings is a mode of infection whichrequires no consideration as a possibility without more supporting evidencethan has yet been advanced.Hodges (190!'l) observed Ff,aria larvae in the thoracic muscles ofthe mosquitoes, Panoplites sp. and Aedes argenteus (Stegomyia calopus),three days after they had been fed on perstans blood. Low (1903) wasable in one case to obtain development of perstans larvae to the sausagestage in a mosquito (Chrysoconops fuscopennatus). Fiillebom (1908,1913) obtained a similar development in Anopheles maculipervnis. Fiillebornand Low obtained negative results with various species of mosquitoes,sand fleas, lice and simuliids.Acanthocheilonema grassii (Noe, 1907) Railliet, Henry andLangeron, 191!'lThe adults of this nematode occur in the subcutaneous and intennuscularconnective tissue and peritoneal cavity of the dog. The larvaeproduced by the f~males are unusually large, about twice as· long andthick as the average filaria larva, and according to Noe (1907, 1908)do not pass into the blood stream as is generally the case among thefilarias. N oe assumed that the larvm are restricted to the lymphaticsystem, and accordingly concluded that the intermediate host would mostlikely be a tick or similar slow feeding ectoparasite. In fact he foundnematode larvae corresponding to those of A. grassii in Rhipicephalussanguincus, a tick of common occurrence in regions where the dogs areinfested with the nematode in question. Furthennore he states that allof the ticks attached to dogs infested with t.he nematode become infestedwith the larval worms. Additional evidence that R. sanguineus acts asthe intermediate host is that the la'rvae in the ticks undergo growth anddevelopment, at least one molting period having been observed betweensuccessive stages. As R. sanguincus is a tick which falls to the ground totransfonn from the nymphal to the adult stage, the necessary opportunif'yis afforded for the transmission of A. grassii from one dog to another.Noe remarks that the nymph of this tick ingests large quantities oflymph. The larval nematodes taken in with the ingl'sted lymph penetratethe intestinal wall into the body cavity where they undergo the develop·