ENTOMOLOGY

"16 SANITARY ENTOMOLOGYment necessary before they are ready to be returned to the definitive 'host,after transformation of the nymphal tick to the adult stage. Noe believesthat the dog becomes infected during the initial phase of attachmentof the adult. He also' suggests that adult males which, unlike adultfemales, may pass from one host to another are capable of acquiringinfection from one dog and transferring it to another. He has foundas many as ~~ larvae of A. grassii in one male tick. Noe is of theopinion that the larvae escape through thin portions of the cuticle ofthe mouth parts of the tick and thus reach. the final host in a way similarto that followed by the larvae of D. immitia and other filarias transmittedby mosquitoes. .It is of interest to note that Grassi and Calandruccio (1890) foundlarval nematodes in Rhipicephalus siculus (=R. sanguineus) which theyidentified as the larval of Filaria recondita (=Acanthocheilonema reconditum).Noe thinks that these larvae may have been A. grassii ratherthan A. reconditum.Evidently further investigations into the life history of A. grassii a.renecessary before ticks can be accepted as the intermediate host of thisparasite.Acanthocheilonema reconditum (Grassi, 1890) Railliet, Henry andLangeron, 191~ .This nematode is a parasite of the dog and in the adult stage has beencollected from adipose tissue in the neighborhood of the kidney. Accordingto Grassi and Calandruccio (1890) the first-stage larvae occur in theblood stream, and are the so-called Haematozoa of Le\vis which havebeen seen by many observers, first by Gruby and Delafond (1843), afterwardsby Lewis and others. Apparently, however, the larvae seen inthe blood of dogs by Grassi and Calandruccio as well as those knownas Lewis's Haematozoa are in reality the larvae of Dirofilaria repens.Grassi and Calandruccio describe various stages of nematode larvaefound in fleas (Ctenocephalus canis, C. felis, and Pulex irritans) and in a.tick (Rhipicephal1L8 sicul1L8=R. sanguineus) as developmental stages inthe life history of A. reconditum. According to Noe (1907, 1908), thelarvae found in R. sanguineus by Grassi and Calandruccio were probablythose of Acanthocheilonema grassii.Owing to the confusion existing with reference to the identity of theparasite that Grassi and Calandruccio studied, the species to which thelarval nematodes observed in fleas belong, is uncertain. Grassi and Calandruccio'sexperiments can not'be considered conclusive so far as concernsthe life history of A. reconditum.