THE CONCHUELA. 43 



the limits of the alfalfa field. The fourth-instar nymphs were found 

 in abundance on fence posts, tree trunks, cotton plants, and weeds 

 within 10 yards of the alfalfa field where they originated, and were 

 scarce from 10 to 20 yards from this field. Nymphs in the fifth instar 

 invaded a cotton field up to about 30 yards, in numbers estimated to 

 average between ten and fifteen per plant; from 30 to 40 yards, 

 between ^Ye and ten per plant; and from 40 to 60 yards, between 

 two and ^Ye per plant. Few, if any, attained a distance of more than 

 60 yards from the point of origin. In these estimates due allowance 

 has been made for the nymphs which occurred in the field before the 

 beginning of the migration. These records do not show the maximum 

 distance which the nymphs are capable of crawling, for the new food 

 supply immediately adjoined the field of original infestation. It 

 is certain, however, that this distance is over 60 yards. 



Adults, 

 fertilization. 



Laboratory observations show that males of the conchuela are 

 polygamous and females polyandric. During copulation in the cot- 

 ton fields, both insects are usually engaged in feeding on a boll or 

 other part of the plant. No attempt has been made to ascertain how 

 long a pair of the insects remain in coitu, but in 2 instances a note 

 was made of more than one-half hour or more than 2 hours, respec- 

 tively. With other species of Pentatomid bugs, pairs have been 

 observed in coition for. a period of several hours at a time. 



EGG LAYING. 



Place of deposition. — Eggs are deposited in batches or clusters 

 wherever the female happens to be feeding or resting. On cotton they 

 have been found on both upper and lower surfaces of the leaf, though 

 more commonly on the latter, also on bracts of bolls and on stems. 

 In a cotton field at Llano, Tex., in September, 1905, a female con- 

 chuela was observed depositing a batch of eggs on lint in an open boll. 

 On grape, 11 batches of eggs collected on July 12 were deposited as 

 follows: 8 on underside of the leaves, 1 on the upper surface of the 

 leaf, and 2 on the tendrils. Of 9 egg-batches collected on July 17, 

 4 were on the underside and 3 on the upper surface of alfalfa leaves 

 and 5 on the underside of a solanaceous weed, the 'Hrompillo" of the 

 natives of Mexico. At Barstow, Tex., eggs of the conchuela with 

 eggs of another Pentatomid which will be referred to later — Penta- 

 toma sayi Stal — were frequently found on the seed-clusters of alfalfa, 

 a favorite feeding place. In captivity the females of the conchuela, 

 as well as other cotton-feeding Pentatomids, deposit eggs usually on 

 the cotton bolls supplied for food, but occasionally on paper at the 

 bottom of the cage and on the cheese-cloth cover at the top. 



