June 4,1917 
The Pink Bollworm 
359 
Station in Honolulu, and Dr. Fullaway agrees that this might well have 
been from a stray mature larva which had accidently crawled into a 
cracked milo fruit for pupation. In order to test the record, the writer 
collected fruits in all stages from the milo trees on the Experiment Sta¬ 
tion grounds as well as elsewhere during the summer of 1915, examining 
many hundred fruits and keeping as many more in cages. Not a single 
pink bollworm was found in or reared from these fruits, although from 
50 to 500 reared moths were liberated every week during the summer 
in and under the trees in an effort to have them oviposit there. 
Similar observations were made with the fruits of other malvaceous 
plants, particularly the hau ( Pariti tiliaceum) and the wild hibiscus 
(Hibiscus arnottianus). Large lots of the fruits were collected and 
examined for larvae, and other lots were placed in rearing jars in an 
effort to substantiate the statements that they are food plants of the 
pink bollworm, but not a single specimen was either reared from or 
found in these fruits. The fruits of hibiscus in Hawaii harbor a micro- 
lepidopterous larva about the same size as the pink bollworm, and this is 
presumably the foundation for the statement in Hawaii; but these 
larvae belong to a different insect, (Crocidocema) Eucosma marcidellus 
Walsingham. 
The pink bollworm, on the other hand, was most unexpectedly found 
in and reared from Gossypium tomentosum , the small dry fruits of which 
seem quite unsuitable for the species. This species of Gossypium is 
indigenous to the Hawaiian Islands. 
Among the several varieties of cultivated cotton, the pink bollworm 
seems to have no choice. The perennial Caravonica cotton is by far 
the most commonly cultivated variety in the Hawaiian Islands; but 
the bollworm attacked just as readily plots of Chinese, Sea Island, and 
American Upland cotton growing in the Agricultural Experiment Station 
grounds in Honolulu. 
. PARASITES 
The larva of P. gossypiella is so effectively protected within the green 
boll that no parasite at present found in the Hawaiian Islands can reach 
it as long as the shell is intact. It is only after the boll has opened or 
after the larva has bored its exit hole through the husk that parasites 
can gain access to it. 
The following five species of hymenopterous parasites were reared in 
Honolulu during the summer of 1915 from P. gossypiella , but none of 
these is an effective check on the pest, and, all combined, they do not 
infest more than a small percentage: Chalcis obscurata Walker; Stoma - 
toceras pertorvus Girault; Pimpla (Itoplectes) hawaiensis Cameron; 
Chelonus blackburnii Cameron; Parisierola emigrata 1 Rohwer. 
1 A closely allied species. Parisierola nigrifemur Ashmead, is parasitic on the pink bollworm in Brazil. 
Maxwell-Eefroy (17) records Apanteles depressariae as parasitic on P. gossypiella in India, and Willcocks 
records (33) Pimpla sp. and (34) a braconid parasite from Egypt. 
94350°—17 - 2 
