﻿STRAWBERRY ROOTWORM ON GREENHOUSE ROSES 



9 



Although Dejean {8, p. Ji.12) used the name gilvipes for a species of 

 Metachroma in his catalogue of Coleoptera, its use is held invalid 

 because of the absence of description or reference to any type; and 

 since Crotch (7, p. 39) was the first to use distinguishing charac- 

 teristics for this variety, the authorship of the name is credited to 

 him. Crotch lists gilvipes as a variety of Paria sexnotata with the 

 very brief description: "Entirely black, legs pale." The name is 

 evidently derived from gilvus (yellow) and pes (foot) and refers 

 to the pale yellowish legs. 



Horn {16^ p. 208) indicates that the head of gilvipes is black, 

 but Blatchley {2, p. 1139) shows that it may be reddish, and also that 

 the antennae as well as the 

 legs are pale. The writer 

 has found that the head is 

 reddish in all specimens of 

 gilvipes observed, and also 

 that the black of the 

 elytra grades into a pale 

 Van Dyke brown color 

 near the tips. 



All individuals of both 

 varieties of the beetles 

 found in the greenhouses 

 have been of a uniform 

 size, and no differences 

 have been noted among 

 specimens from the several 

 widely separated infesta- 

 tions. The length ranges 

 from 2.8 to 3.6 millimeters 

 and the width from 1.0 to 2 

 millimeters. It is interest- 

 ing to note, however, that 

 specimens of the same va- 

 rieties which had been col- 

 lected out of doors were 

 much larger, being 4.5 mil- 

 limeters long and 2.3 milli- 

 meters wide. 



When the beetles are first transformed from the pupae they are 

 very light in shade, but upon exposure to the air soon acquire the 

 normal coloration and markings. The ventral surface of the body 

 becomes black in both varieties. 



The four-spotted variety, quadrinotata (fig. 3), has been more 

 prevalent in greenhouses, and was encountered in every infestation 

 observed; but the closely related gilvipes^ with its black body and 

 pale legs, has also been found simultaneously in several establish- 

 ments in considerable numbers. Practically all of the observations 

 on the adult were made on individuals of the variety quadrinotata. 



CAGE FOE OBSERVATIONS ON ADULT STAGE 



The type of cage used for most of the observations on the adult 

 stage was a glass vial or test tube 1 inch in diameter and from 3 to 5 

 52018—26 2 





Fig. 



3. — The strawberry rootworm. 

 variety quadrinotata 



Adult of the 



