NOTES AND OBSERVATIONS. 31 



(Men. Pterom. 235) : " In Coccis pruni gregariiim legit Geerus " 

 {rf. De Geer, Ins. ii. 190). Eatzeburg found his Encijrtus cocco- 

 piiagus to be the chief parasite of Coccus pruni (Ichn. cl. Forst. 

 ii. 148). The only species bred from it by Mayr (Verb. z.-b. 

 Ges. 1875, p. 206) was Microterys sylcius, Dalm., which has 

 since been also raised in the United States of America. Gaulle 

 adds M. lunatus, Dalm., Eucomys scutcllata, Swed., and, from 

 " Coccids of Prunus," Ericydnus longicornis, Dalm. 



(To be concluded.) 



NOTES AND OBSERVATIONS. 



The Taps of the " Death Watch Beetle." — Stephens says 

 in his 'Manual' that Anohium striatum, Oliv., is to be taken from 

 April to August ; and doubtless most coleopterists would be quite 

 willing to accept the statement as correct, because the species is so 

 common that few have troubled to notice its times of occurrence. I 

 have recently been jotting down notes upon the Braconidous parasite 

 of this injurious beetle {Spathius exarator, Linn.), and was surprised 

 to note that both host and parasite put in no appearance till July 

 3rd, when both began to be very common on the posts in my stable 

 here. On referring to the series of this species in my collection — 

 which is not complete — I find that the dates range only from 

 June 21st to July 15th ; it would be of interest if coleopterists 

 would give us their experience of the span allotted to perfect A. 

 domesticum. 



It was, consequently, with some surprise that I heard the familiar 

 tapping of this beetle in an old oak bureau, I had but just acquired, 

 in my study on October 16th last, and, bearing in mind the state- 

 ment made in a recent popular article on the insect to the effect that 

 only four or five taps were given in succession — it had struck me as 

 incorrect when I read it ('Strand Magazine,' 1909 (Oct.), p. 475; 

 a similar statement is made, if I remember aright, by Darwin in 

 'Origin of Species') — I drew my watch and awaited a repetition. 

 The first series of taps had occurred at dusk ; and I caught the 

 second at 5.23 p.m. ; this lasted from seconds 48-57, and was 

 followed by other series of continuous taps at intervals of less than 

 a minute thus : — 37-52, 23-33, 5-15 ; then came over a minute's 

 silence, and after it : — 35-44. Next came a longer interval of silence, 

 lasting from 5.28 to 5.32, followed by a last succession of taps :— 20- 

 28. No more were heard that night, nor since. 



I attempted to count the taps, but they were too numerous ; 

 often one is enabled to count such quick successions of sound by 

 simply listening to them in the first place and afterwards counting 

 them by repeating the sound over again more slowly ; but this was 

 too quick, and I could do no more than guess the number to be 

 approximately thirty or forty. Everyone is familiar with this por- 

 tentous hammering of one's coffin nails (they used nails when 



