AKT.IO THE FAMILY SIMULIIDAE— DYAK AND SHANNON 19 



second tarsus without dorsal incision; abdominal dorsal plates 

 broader than lon^-. 



Hypopygium : Cerci rounded quadrate, transverse. Xintli sternite 

 triangular normal, more heavily chitinized on its posterior border, 

 setae absent on lower border. Ovipositor valves slight, thin. Forks 

 of genital rod widely divaricate, expanded, each with a large ir- 

 regular double or triple tooth. (Fig. 37.) 



E. pecuunim has been recorded from Westville, Conn., and lona, 

 X. J. Specimens from the former locality are not at hand and the 

 specimen from lona proves to be mutatum. Another specimen from 

 New Hampshire placed with peemru?7i in the collection proves to 

 be P. hirtipes. It has also been reported from Illinois. This may 

 be inven'mtmn Walker, but we have no positive information. One. 

 hundred and ninety specimens at hand. 



Type localities. ~Oi invenmtum. —Ks^vims Fall, Ontario. The 

 type is in the British Museum. The junior 

 author examined it in August, 1925, and found 

 it to have the characters of peeuarum or daco- 

 tense. A third species may possibly be repre- 

 sented, so we refrain from a positive reference. 

 Of peeuarum. — Somerset Landing, La. The type 

 is in the IT. S. National Museum. Cat. No. 772, 

 U.S.N.M. 

 DiM?ibiUimi.~AiiKA-ssA^: Manila (M. M. Hinesly). 



Louisiana: Somerset Landing, April 10, 1886 

 (F. M. Webster). Mansura, Februarv 24, 1910 

 (C.E.Wood). 

 Mississippi: Lake Horn, March 16-May 6, 1886 

 (F. M. Webster). Lake View, April lO-Mav 4, 

 1886 (F. M.Webster). 

 Texas: College Station (F. M. Webster). 

 Eushnulium pecuarunh (Riley) for a long series of years during 

 and following the Civil War was an unusually serious menace to live- 

 stock and even to human beings along the lower Mississippi. Great 

 numbers of cattle and mules perished as a result of their attacks. No 

 serious outbreaks have occurred during the past 30 to 40 years. 



The late Francis M. Webster accounted for this thus: The reason 

 for these particularly severe outbreaks and their absence in recent 

 years is accounted for by the fact that prior to the Civil War the 

 hvees of the Mississippi w-ere in good condition and continuous 

 tlirough all of the alluvial country of the lower Mississippi: but 

 with the outbreak of the war the levees were neglected and in many 

 cases caved in. The adjoining lands became flooded, making ideal 

 bi-eeding conditions for the black flies. During the war the plagues 

 of Buffalo gnats became so <rreat and so severe that the Cavalrv 



