RKAUIN(i I.ARV.K OX rK< >LI KKHOT'S FOOD. 35 



CONCl.rsiONS. 



Sovoral important and ()l)vi()us conclusions may be drawn from tho 

 results of the artificial stinuilation of ])rolifcration. Proliferation in 

 buds and bolls does not de])end essentially for its stimidation upon 

 insect injury of any particularkind. Tt IxH'omes unnecessary to assume 

 tlial any irritatin*; secretion is de])osited by tlie weevil with the etj:g. 

 It has \)eon sliown conclusively that proliferation may occur entirely 

 apart from weevil ])resence. Troliferation may r(>sult from a lar*i;e 

 number of causes, of which tlie followhii; are noted in this bulletin: 

 "Weevil feedin^: punctures, weevil egg; punctures, injury by the larva 

 durini: its feedin*; ]>eriod, bollworm ])imctures, s([uai'e-b()rci- ])unctures, 

 feedini:; ])unctures of various bugs, fungous attacks in insect ])unctures, 

 anthracnose, and artificial punctures of the bud or boll. 



MANNER IN WHICH PROLIFERATION CAUSES DEATH OF 

 WEEVIL STAGES. 



REARING LARVJC OX PIRELY PROLIFEROUS FOOD. 



In order to determine whether proliferation caused the death of 

 larva* by starving or poisoning them, numerous ex])eriments have been 

 performed. Unhatched eggs and larvje just hatched have been placed 

 in the midst of masses of pun^ly ]>roliferous formati(m; and these have 

 been kept in a tight, moist chamber and transferred to fresh masses 

 of ]>roliferation as frequently as necessary to preserve proper condi- 

 tions for tlie larvfc. In spite of these frequent transferences and the 

 somewhat unnatural conditions necessary, it was found that but a very 

 small proportion of the larvae died. In some cases the growth was 

 completed in masses of ]>roliferation which were comjiletely decayed. 

 This condition was allowed to exist in order to test the elTect of what 

 seemed the most unfavoralile food conditions it was ])ossibl(' to ])ro- 

 duce so far as quality was concerned. In oii(> .series of experiments 8 

 ver\'young larvte wen* ])lace(l in fresh i)roliferous masses. Of these, 1 

 died on the first day, but all others reached full growth and ])upated 

 normally in from nine to twelve days, luiving fed on nothing but ]>ro- 

 lifcrous material. 



In allot her series S larva^ just hatched were started in locks in which 

 dead full-grown larva* had been found entirely enveloped by the ])ro- 

 liferation. Surely if ])roliferation were ])oison()Us, this test should 

 prove it, since in each <-ase a lar\a had been ]>re\iously kill(Ml in the 

 lock given each young larva for food. 



One larva was accidentally killed in examining the material on the 

 fourth day. One larva coiuplrted its giow th and pupated in the lock 

 in which it was originally ])laced. Two died and the remaining 4 

 also pu|)ated after being transferred to fresh locks from which dead 

 larva' wi-re ])reviously taken. I nder these most unpromising condi- 



