THE DEVELOPMENT OF THE FRENULUM OF THE WAX 
MOTH, GALLERIA MELLONELLA LINN. 
WILLIAM S. MARSHALL. 
The following quotation is taken from Comstock’s (6) recent 
book on the wings of insects: 
“In most moths there is a strong spine-like organ or bunch of 
bristles borne by the hind wing at the humeral angle: this is the 
frenulum or little bridle. As a rule the frenulum of the female con¬ 
sists of several bristles; that of the male, of a single strong, spine-like 
organ. In the males of certain moths, where the frenulum is highly 
developed, there is a membranous fold on the fore wing for receiving 
the end of the frenulum thus more securely fastening the two wings to¬ 
gether: this is the frenulum hook.” 
Griffith (9) has given an account of the frenulum in the Lepi- 
doptera, and the following historical remarks are in part ex¬ 
tracted from his paper. De Geer (7) in 1752 was the first to 
describe the frenulum; he records finding it in all the species of 
noctural Lepidoptera he examined. He failed to notice its pres¬ 
ence in the females, and, although he recognized its ability to 
hold the fore and hind wings together, he was uncertain as to 
its use. Harris (10) in 1767 described and figured the frenulum; 
he observed its presence in the males only, but he found that the 
female moths had four small bristles instead. Giorna (8) listed 
seventy species of moths in which the males possess a frenulum; 
he called attention to a corresponding structure present in the 
females of many species of the moths he examined. References 
to the frenulum are found in Burmeister (2), Westwood (15), 
Poey (13), etc., etc. The last mentioned entomologist found that 
the frenulum is simple in the male specimens but multiple in the 
female. Chenu (3) held that the frenulum is used to hold the 
wings in a horizontal position during repose. 
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