1911] Study of Muscoid Flies 137 



ly wide, flat below; wide and short when contracted. The habit 

 is larviposition, but one can not even guess at the larval habit 

 and host relation. This is a most interesting and remarkably dis- 

 tinct type. Although the Colorado and Veracruz specimens of 

 the fly look quite alike externally, the maggots from the Vera- 

 cruz specimen all show two large black bunches of strong more 

 or less swollen and hooked or cleft spines on cephalic segment 

 which are wholly lacking in the maggots from the Colorado 

 specimen, indicating two very distinct species. The maggots 

 from the Peruvian specimen do not show these cephalic spine- 

 bunches; they besides differ from both the Colorado and Vera- 

 cruz maggots in the characters of the segmental plates. 



The Veracruz specimen came from Orizaba (coll. by Herbert 

 Osborn) and is probably P. bilimeki B. B., the type of which 

 came from the same locality. A much fuller description with 

 figures of the maggots and female reproductive system will be 

 given in forthcoming papers. 



32. Megaprosopine series — Microphthalma spp. (North 

 and South America) dissected, TD 313, 3915. Uterus pres- 

 ent, long, subtubular, in several coils, filled with thousands of 

 slender pointed eggs and maggots. The maggot of Microph- 

 thalma is very hairy, being the extreme development in this 

 respect so far as known. This series includes Microphthalma 

 and allies, and almost certainly Megaprosopus. Trixodes is 

 almost certainly the type of a separate series. The first and 

 probably the second are white-grub parasites, while Trixodes is 

 probably a woodboring-grub parasite. 



33. Macronychniine series — No dissections of Macrony- 

 chia have as yet been made. The uterus may well be Meto- 

 piine in form. At all events it must be quite distinct from the 

 preceding series. The forms are perhaps muddauber-wasp 

 inquilines. 



34. Cuterebrine series — Cuterebra spp. (Florida and 

 South Carolina) dissected, eggs drawn, TD 487, 486. Probab- 

 ly no uterus, as the eggs are certainly deposited ; chorion of egg 

 very thick and hard, furnished at what is probably cephalic- 

 end and with a hinged lid or cap opening on dorsal aspect of 

 ■egg and provided for the exit of the maggot which could not 

 otherwise escape from its heavy chorion-prison, thus demon- 

 strating most conclusively that the egg is intended for deposi- 

 tion as such. Eggs probably deposited externally on skin or 



