144 Annals Entomological Society of America [Vol. IV, 



cylindrical, and appears to lie curled in the sub-circular or oval 

 egg. Pressure on the egg often causes it to assume an elongate 

 narrow form pointed at ends, inside which the maggot probably 

 lies straight. Slight pressure or teasing with a needle causes 

 the cylindrical anterior portion of the maggot to protrude from 

 the ventral edge of egg, at right angle to long axis. I can see no 

 difference in the maggots from the short and long uteri, and am 

 constrained to believe that here the uterus gradually increases 

 in length as the eggs descend from the ovaries and fill it, although 

 oviposition may begin while the uterus is still short. If this is 

 so, it is an exceptional case in the great increase of length after 

 maggots have become fully formed within the choria. There 

 seem to be two forms of the flies in the Peruvian material, dis- 

 tinguishable externally, but the separation does not accord with 

 the uterine difference. One or both of these forms are prob- 

 ably what has been called Gonia chilensis. 



My dissections have shown Gonia frontosa (Mass.) to have 

 a long coiled uterus; and what I identify as G. pallens and G. 

 angusta (S. Florida) to have a very long uterus. The chorion 

 of the egg is the same in these forms as above described. 



The above observations indicate that much care and judg- 

 ment must be used in describing the female reproductive organs 

 in these flies. I have noted variations in lengths of uterus 

 in other forms within certain limits ; and variation in the number 

 of rows of eggs in the strap-like forms of uterus as well as in 

 certain others, without a corresponding variation in length. 

 It is evident that we need careful investigations in various 

 groups which shall determine how many days elapse between 

 issuance of the fly or fertilization and complete development of 

 the female reproductive organs. I have noted that in Vari- 

 chaeta, under artificial conditions, this takes about fourteen 

 days. 



Phasiatactine series — Phasiatacta elongata gen. et sp. 

 nov. (Peru) dissected and drawn, TD 4019. Uterus extremely 

 long and slender, in very many coils and irregular turns, preu- 

 terus present. Ovaries large, oviducts long and slender, sper- 

 mathecal ducts long and curved, tubular glands elongate. Eggs 

 black, elongate, pointed at each end, chorion with areoles gath- 

 ered around a dorsal opaque area, without reticulation. 



Cnephalomyiine series — Cnephalomyia floridana gen. et 

 sp. nov. (So. Fla.) dissected, TD 877. Uterus very long and 



