102 MISCELLANEOUS PAPERS. 



long tubules which lead to the three sperniathec.ie or seminal vesicles. 

 The latter receive the male fluid at the time of union of the sexes. 

 The point of opening of the spermatic tubules marks the termination 

 of the oviduct, immediately below which begins the long, tube-like, 

 coiled uterus. 



Upon dissecting dead females of Parexorhta chelonkv the uterus of 

 certain of them was found to be packed not only with eggs but also 

 with living maggots. The latter occurred at the lower end of the 

 uteius next the ovijiositor. As many as three hundred such eggs and 

 maggots were found in the uterus of one clwlonhv. This explained 

 why no definite period of time could be ascertained for the hatching of 

 the ^^2^ of chclonkv after its date of deposition. Some of the eggs 

 hatched almost immediately after being laid upon the caterpillars, 

 while others did not hatch for a week. After making this observation 

 we realized that some of our species might be expected to deposit 

 living maggots. 



DEXODES NIGRIPES Fallen and COMPSILURA CONCINNATA Meig-en. 



The expectation that some species of Tachinida* would deposit 

 living maggots was innnediately realized in the next species taken up, 

 Dexodes nigripes Fall., a common summer-issuing species reared from 

 l)otIi Euproctis chrysorrhoea and Poi'tlietrla dispar. The uteri of the 

 females of nufripe^ Avere commonly found to contain living maggots, 

 and these were apparently deposited, not on, but inside the skin of 

 caterpillars of both E. rhri/son'hoea and Tlenicrocanipa Icucostkjnui 

 S. & A., and reared to the puparium in both. A very similar 

 species, Compxiliira conciniiatd Meig., apparently has the same hal)it 

 of depositing living whitish maggots inside the skin of the cater- 

 pillars, and was reared in small caterpillars of chrijsorrhma from 

 cold storage, not only to the puparium, l)ut to the fly as well, thus 

 proving at least three l)roods in one season for this species. It should 

 also be stated that the above puparia of De.rodcs nu/ripes similarly 

 gave issuance to the flies, thus proving that it also has at least three 

 broods. 



The very remarkable point brought out in the investigation of these 

 two species is that the females of both are provided with a long curved 

 sheath, into the base of which the ovipositor fits, and which tapers 

 to a microscopically sharp point. With this organ the females evi- 

 dently puncture the skin of the caterpillars at the moment of larvipo- 

 sition, introducing the living maggot within the skin of the host. 

 Such a habit was never suspected in the Tachinida\ We have exam- 

 ined native species which are furnished with the same sheath and 

 must have the same habit. 



