PTINUS. 
34 
o-no-ed in the more imnortant cares of providing 
the immediate necessaries of life should have 
either leisure or inclination to investigate with 
philosophic exactness the causes of a particular 
sound: yet it must be allowed to be a very sin- 
mdar circumstance that an animal so common 
O 
should not be more universally known, and the 
peculiar noise which it occasionally makes be 
more universally understood. It is chiefly in 
the advanced state of spring that this alarming 
little animal commences its sound, which is no 
other than the call or signal by which the male 
and female are led to each other, and which may 
be considered as analogous to the call of birds; 
though not owing to the voice of the insect, but to 
its beating on any hard substance with the shield 
or fore-part of ite head. The prevailing number of 
distinct strokes which it beats is from seven to 
nine or eleven; which very circumstance may 
perhaps still add in some degree to the ominous 
character which it bears among the vulgar. These 
sounds or beats are given in pretty quick suc- 
cession, and are repeated at uncertain intervals ; 
and in old houses where the insects are numerous, 
may be heard at almost every hour of the day ; 
especially if the w^eather be wairm. The sound 
exactl)^ resembles that wdiich may be made by 
beating moderately hard with the nail on a table. 
•The insect is of a colour so nearly resembling that 
of decayed wood, viz. an obscure greyish browm, 
that. It may for a considerable time elude the 
search of the enquirer. It is aboujt a quarter of 
