122 THE ENTOMOLOGIST. 



the book-louse or of the beetle. All that he did was, when 

 describing T. pulsatorium, to mention the fact of its ticking, 

 although he may possibly have heard it himself ; and since he 

 gave a reference to Derham, he doubtless considered his own 

 species to be the same as Derham's Pediculus imlsatorms, with 

 regard to whose ticking there could be no manner of doubt. 

 Mr. Kemner himself it is who has made the mistake, and I 

 fancy it is not his only mistake on the subject. For he states 

 also that A. striatum, when ticking, gives fifty to sixty beats in 

 succession before it stops to make a pause of a second or more. 



It is, to say the least, very doubtful whether A. striatum, 

 Oliv., ticks at all. And I doubt even whether A. pertinax, Linn,, 

 is a ticking beetle, notwithstanding the observations of Herr 

 Schmid, and the statement made by Mr. Kemner, on what 

 authority he does not say, that this species gives seven or eight 

 taps in succession, just as does the well-known "death-watch " 

 Xestohium ruforillosum, De Geer ( = tessellatum, Oliv.) . 



A. pertinax, Linn., is a species that does not occur in this 

 country, and few British entomologists are familiar with it in its 

 living state. With the exception of Schmid, I do not know of 

 any writer who has spoken about its ticking from direct observa- 

 tions made by himself, although many coutinential writers have 

 referred to the species as one of the death-watches. Until there 

 is better evidence of it, I shall continue to doubt its ticking. 



In reference to the ticking of A. striatum, Oliv., we are better 

 qualified to form an opinion. This species is very common here, 

 and there is scarcely a house in which it is not present in some 

 old piece of furniture or, if the house be old, in the woodwork. 



How many British entomologists have ever seen it tapping ? 

 I don't know of one. Many have said that it taps, and have 

 ranked it amongst the death-watches. Kiiby and Spence have 

 said so, Westwood has said so, a dozen or more have said so, 

 and I may even have said so myself, but then I should only have 

 been repeating what had been said so often before without 

 questioning the authority for it. Continental entomologists 

 have been almost as unanimous in their statement about the 

 ticking of that species, and Reitter even refers to it as " the 

 death-watch beetle." 



I have tried to find some account of the tapping of A. striatiwi 

 that was based upon actual observation of it, but I have succeeded 

 so far in finding only one, which is said to be based upon observa- 

 tions made by Latreille, the great French entomologist. 



In ' Rapports generaux des Travaux Soc. Philom. Paris,' 

 tome iv, p. 67 (1800) it is stated that ' He [Latreille] also read 

 a memoir upon la vrillette striee and on the manner in which it 

 produces the sound it makes heard ; it is not the larva which 

 causes this noise, but the perfect insect, which citizen Latreille 

 has seen to strike upon the dry wood with its mandibles, and the 



