JOURNAL 
OF 
ECONOMIC ENTOMOLOGY 
OFFICIAL ORGAN AMERICAN ASSOCIATION OF ECONOMIC ENTOMOLOGIST 
Vol. 16 AUGUST, 1923 No. 4 
THE POSSIBILITY OF TRANSMITTING A CALENDRA 
INFESTATION FROM WHEAT TO MACARONI THRU THE 
PROCESSES OF MILLING AND MANUFACTURING 1 
By Royal N. Chapman, Division of Entomology and Economic Zoology , 
University of Minnesota 
Abstract 
The question of whether or not a granary weevil infestation could pass directly from 
the wheat to the macaroni has been of great practical importance to the milling and 
macaroni industries. In the experiments described in this paper it was shown 
that ( 1 ) no stage of the weevil could survive the process of milling the durum wheat into 
Semolina from which the marcaroni is manufactured. Even the eggs were unable 
to survive this process, ( 2 ) that the adult weevils would not oviposit in the semolina, 
(3) even if the weevils or their eggs were present in semolina they could not survive the 
process of manufacturing the macaroni. It was also found that the weevils are intro¬ 
duced into the factory and lay their eggs on the macaroni while it is drying. 
Introduction 
There has been no question that the weevils which attack macaroni 
are the same ones which attack wheat as cited by Zacker, Cotton, 
Teichmann and Andres and others, but it has never been determined 
whether these weevils pass through the processes of manufacture and 
thus infest the macaroni, or whether the weevils must enter the macaroni 
in the same way as they enter the wheat, namely by ovipositing in it. 
The fact that the weevils do lay eggs in macaroni is well known, but 
their ability to survive the milling of semolina and the process of manu¬ 
facturing macaroni has been the object of these experiments. 
The possibility of the weevils surviving the milling process is de¬ 
pendent upon the ability of the eggs to remain unbroken during the 
process of milling. Since these eggs are slightly smaller than granules 
of No. 2 semolina, it is a question as to whether the wheat would break 
in such a way as to leave the egg in the center of a granule. This is a 
matter of the chance of a granule breaking off without the line of cleavage 
following the cavity in which the egg was laid. 
Published with the approval of the Director as Paper No. J 47 of the Journal 
Series of the Minnesota Agricultural Experiment Station. 
341 
