The Ohio i!\£aturalist, 
PUBLISHED BY 
The Biological Club of the Ohio State University. 
Libras 
new YO 
3otanic| 
OARDEi 
Volume X. NOVEMBER. 1909. 
No. 1. 
TABLE OF CONTENTS. 
Matheny— The Twig Girdler 
Schaffner— An Interesting Botrychium Habitat 
Schaffner— The Gymnosperms of Ohio 
Jennings— The Labrador Tea in Ohio 
Cook— Potato Agar 
News and Notes 
Osborn— Meetings of the Biological Club. 
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8 
9 
13 
13 
14 
15 
THE TWIG GIRDLER.* 
W. A. Matheny. 
Oncideres cingulatus (Say) . Order Coleoptera ; family Cerambycidae. 
“A thick-bodied longicorn, dark gray beetle about .5 inch long, with 
its wing-covers sprinkled over with faint tawny yellow dots.” 
In making a study of the galls of this community during the 
fall of 1907, I came across the work of the ‘‘Twig Girdlers.” 
These singular beetles appear in Ohio from the middle of August 
until the middle of September. Figure 1 represents the beetle 
and the incision it makes. According to Slingerland, this beetle 
always works head downward. This would discredit the draw- 
ing by Riley. Prof. Glenn W. Herrick says, in his paper on “The 
Pecan Pruner’’ (O. texana Horn.) that the beetle works head 
downward. 
Professor Haldeman states that “both sexes are rather rare, 
particularly the male, which is rather smaller than the female, 
but with longer antennae.’’ The female does all the work. 
She makes perforations (Fig. 1, b) in the branches in which she 
deposits her eggs (one of which is represented of the natural size 
at Fig. 1, e.) She then proceeds to gnaw a groove, of about a 
tenth of an inch wide and deep, around the branch and below 
the place where the eggs are deposited so the exterior portion dies 
and the larva feeds upon the dead wood. 
Mr. James Brodie describes the manner of cutting of the 
0. texana as follows: 
“In starting work, a patch the desired width of cut is cleaned and 
the bark eaten. Then the powerful mandibles are brought to work on 
the wood. A cut is first made at the top, then the head moves down to 
* Contribution from Biological Laboratory, Ohio University. 
