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the fat-contents of which the parasite has sucked out, and 

 the cells are then pressed together around it (Fig. 5 s). 

 Around the sac a more or less dense and complete layer of 

 leucocytes is found (Fig. 1 1, 3 1, 6 1.) and leucocytes are 

 also gathered around and between the hypoderm- cells on 

 the outside of the funnel, and here they cause the coating 

 of cells to increase in thickness. 



The parasite feeds exclusively on the contents of the 

 fat-cells until it gets to the third stage; it does not other- 

 wise attack the organs of the host, but during growth it 

 compresses the intestine of this (Fig. 6 t). When the parasite 

 is nearly fuUgrown it ruptures the sac, and this, together 

 with all the organs of the host are destroyed and sucked 

 up by the parasite (Fig. 7). At the same time the host 

 dies, and the parasite draws its posterior end out of the 

 chitinous funnel. Next the boring out of the parasite com- 

 mences; this act is begun by the parasite pressing the end 

 of its body against a spot on the empty skin of the host; this 

 spot is then seen to get moist, and by and by the chitin 

 disappears and thus a large, open holeis formed through 

 which the parasite emerges backwards. 



The pupation takes place in the cocoon of the host, 

 and after the course of a month the imago escapes. Only 

 one parasite in each host larva reaches to full development. 

 Together with Ptychomyia, Bactromyia aurulenta Meig. also 

 occurred in the Ht/ponomeuta-]a.r\æ and its habits were quite 

 the same as those of Ptychomyia. 



Panzeria rudis Fall, is viviparous and deposits its larvæ 

 on fullgrown larvæ of Tæniocampa stabilis View. The larvæ 

 penetrate through the integument of the host and their relation 

 to the latter is the same as described above Avith regard to 

 Ptychomtjia ; only the chitinous funnel is somewhat longer, 

 and the parasite feeds nearly exclusively on the fat of the 

 host and spares the intestine until just before it is full- 

 grown. The larva bores its way out through the larval 

 skin of the host and pupates in the ground. The pupæ 

 hibernate, and the iraagos appear in June and July. Only 



