. Bulletin of the Department of Agriculture. Agriculture; Agriculture. TIIK PA HAS IT KS OF P( )|>I A JAPONIGA 37 Three additional molts occur before the final larval stage is reached, and at each one the head is shifted forward and a new feeding punc- ture made. The successive cast skins remain in a leaflike form as a pad beneath the body, serving to attach the parasite larva to the hosl during these stages. There is thus a total of five larval stages, with the eggshell and four cast skins adhering to the final stage. This i- shown diagrammatically in Figure 27. In the last stag
. Bulletin of the Department of Agriculture. Agriculture; Agriculture. TIIK PA HAS IT KS OF P( )|>I A JAPONIGA 37 Three additional molts occur before the final larval stage is reached, and at each one the head is shifted forward and a new feeding punc- ture made. The successive cast skins remain in a leaflike form as a pad beneath the body, serving to attach the parasite larva to the hosl during these stages. There is thus a total of five larval stages, with the eggshell and four cast skins adhering to the final stage. This i- shown diagrammatically in Figure 27. In the last stage feeding is continued at the puncture hole until after the death of the host, when suctorial action no longer suffices and the mandibles are brought into use. The entire body of the host. exclusive of the head and a portion of the legs, is ordinarily consumed, as well as the cast skins of the parasite itself. The presence of the egg or early-stage larva on the body causes no appreciable inconvenience to the host grub, but as feeding advances it becomes weakened through withdrawal of the body fluids. Death of the host occurs when the parasite larva is in the fifth instar and the formation of the cocoon of the latter takes place with- in about two days. The duration of the larval stages varies considerably with the temperature conditions, and ranges from 14 days under high temperatures at Yokohama to nearly a month at Koiwai. Following the completion of feeding, the spinning of the cocoon is immediately begun, and this takes place in situ in the soil cell of the host. The outer covering is of very loose texture, but the succeeding ones are much more compact. The inner surface is very smooth and firm. The meconium of the larva is cast immediately after the completion of spinning and remains as a hard pad at the posterior end. The dormant period is passed in the larval stage within the cocoon, and pupation occurs only a short time prior to the appearance of the adult. The first ad
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