244 ENTOMOLOGICAL NEWS [Oct., '22 



of Manaos, bringing the estimated total of specimens and species of 

 Odonata up to 8315 and 162 respectively. There was much cloudy 

 weather and frequent showers. On July 21 "we collected Agrionines in 

 Mr. Russell's house. They were quite numerous flying about, nosing 

 along walls, furniture, etc., and resting on everything in sight from 

 picture cords to the centre of a bed. Though we have caught some of 

 this species in the house heretofore, they were never so numerous as 

 to-day. Some were netted, many were caught by hand." 



On July 22 the expedition took steamer from Manaos for Para. The 

 Rio Negro had fallen only \ l / 2 feet since its new high water mark and 

 the Amazon was still flooding the country to Para, which was reached 

 on July 29. 



Expectations were that the Expedition would leave Manaos about 

 August 1 for Para, leave Para about September 3 for Rio, arriving 

 there September 17. (From Mr. Jesse H. Williamson's "log" and 

 letters). 



The Stridulation of a North American Noctuid, Heliocheilus 

 paradoxus Grote (Lep.). 



On the night of August 16th, 1921. while at Amarillo, Texas, an 

 effort was made to secure species of Tettigoniidae by listening for their 

 stridulation and then locating the singers with the aid of a hand flash- 

 lamp. A wide grassy plain was visited, but it was soon evident that 

 search would be unproductive. Only a few specimens had been heard 

 and these at widely separated spots. 



While standing in the knee-high grasses all was silent, when suddenly 

 a faint stridulation became audible. Again and again this sound was 

 approached, but nothing could be located. Finally, when undoubtedly 

 close to a singer, a small huffy moth was seen to be hovering in the 

 shaft of our light, just above the weeds and grasses, holding itself over 

 the same spot by flying against the brisk breeze that was blowing. Sud- 

 denly it flew away and the sound ceased. The singer was in fact a 

 moth and not one of the smaller katydids, as had been supposed. 



After this, several specimens were easily secured by following up 

 the sound they produced, all acting just as the first individual had done. 

 The stridulation was like "the ticking of a loud watch, but much faster 

 and easily audible to good ears at a distance of twenty feet." When 

 alarmed a singer would fly away noiselessly and at great speed. 



The species has been, identified by Dr. Henry Skinner as Heliocheilus 

 paradoxus Grote. 1 Stridulating organs for the Agaristidae and Noc- 

 tuidae have been discussed by Dr. Jordan in 1921,- but we know of noth- 

 ing in the literature bearing on the stridulation of the present insect or 

 other North American Noctukls. The species is huffy and not strik- 

 ingly marked. Toward the costal margin of the fore-wings, the highly 

 specialized Stridulating area is found. MORGAN HEBAKU. 



1 Described from Colorado, Proc. Ent. Soc. 1'hila., IV, p. 32'). pi. J, 

 figs. 3 ($), 4 (9), 5 (9, reverse), (1865). 



2 Proc. Ent. Soc. Lond., V, p. xxxiii. 



