THE CONCHUELA. 47 



raises and lowers its head. After withdrawing the setae from the 

 boll, a downv^ard stroke of one of the fore tibise places them in the 

 rostral groove, each tibia for this object being provided with a short 

 spine located on its inner side slightly beyond the middle. 



Miscellaneous observations on feeding Jiabits. — Twenty-six observa- 

 tions gave 20 minutes as the average time the adults fed through one 

 puncture in a cotton boll. The maximum length of time in these 

 observations was 1 hour and 30 minutes. In his report of prelimi- 

 nary investigations " on the conchuela the author presented his 

 observations on the length of time adults remain on a single boll and 

 on a single plant as follows : ' ' One adult under observation in the 

 field visited 4 bolls, 2 on each of 2 plants in 2 days, and remained 

 for over 36 hours on the last of the 4 bolls. Another adult bug 

 remained on the same boll for 2| days. Three remained on the same 

 boll for over 30 hours and 3 others were found on the same plant 

 30 hours after they were first recorded. In none of these cases was 

 it known how long the insects had been on these plants previous to 

 their first being noted." 



Abnormal predaceous and cannibalistic Jiabits. — Starving adult con- 

 chuelas confined with live caterpillars of the boUworm (HeliotTiis 

 obsoleta Fab.) and the cotton boll cutworm {Prodenia ornitJiogalli 

 Guen.) failed to exhibit any indication of carnivorous habits. Dead 

 or dying insects, however, are not always refused and are sometimes 

 fed upon by adults as well as by nymphs in preference to cotton bolls. 

 (See feeding habits of nymphs, pp. 41-42.) On a few occasions where 

 2 or more adults have been confined together in breeding cages, 

 dead or dying specimens have been fed upon by the survivors of the 

 lot. All evidence at hand goes to show that in the field the adult 

 conchuelas are entirely phytophagous. 



GREGARIOUSNESS. 



The gregarious habit exhibited by the conchuela, like its habit of 

 occupying a conspicuous position on the plant, is of considerable 

 importance in its control. The author has previously noted ^ this 

 striking feature, basing the records on observations made at a season 

 of the year when these insects were comparatively scarce. Between 

 August 31 and September 6, 1904, in a selected section of the cotton 

 fields at Tlahualilo, 34 adults were collected on 16 plants, although 

 the insects were so few that but 5 or 6 plants out of 100 were found 

 to be infested. In July, 1905, 2 other species of Pentatomids 

 (Pentatoma sayi Stal and TJiyanta perditor Fab.) were found associated 

 wdth the coirchuela and occurring in moderate abundance on the 



aBul. 54, Bur. Ent., U. S. Dept. Agr., p. 26, 1905. &Loc. cit., pp. 26-27. 



