404 IIHTNCHOPHORA. [Sculytus. 



SCOZiVTUS, Miiller (Eccoptor/aster, Herbst.). 



This genus contains about thirty species, of which about half are 

 found in Europe, and the remainder have been described from North, 

 Central and South America, and from Java ; several of the European 

 species also occur in Northern and Central Asia ; the characters given 

 for the tribe will be sufficient to distinguish this the single genus 

 belonging to it ; the life history of the species is of great economical 

 interest, as the ravages that the beetles commit upon forest and fruit 

 trees are often most serious ; the commonest British species is S. des- 

 tructor, which destroys vast numbers of elm trees throughout the country, 

 whole avenues of fine trees being sometimes ruined by its devastations : 

 the larva of this species is figured by Westwood (Classification I. p. 350, 

 fig. 42, 4) ; it is a thick fleshy grub, of a whitish colour, broader in front 

 than towards apex where it is somewhat narrowed ; the head is corneous 

 and provided with powerful jaws ; the back is much wrinkled, and 

 there are no traces of legs ; a very interesting paper on " Observations 

 of the economy of the British species of Scolytus," was published in the 

 Entomologist's Monthly Magazine (vol. vi. 1869-70, p. 126), by Dr. 

 Algernon Chapman ; this gentleman still continues his valuable observa- 

 tions on the group, and two years ago (November, 1888) I received 

 letters from him regarding certain species ; as the subject is one of such 

 general interest, it may be of service to quote a portion of his remarks 

 at length, more especially those referring to S. destructor, concerning 

 which he says: " This, the commonest of our species, may be found 

 early in June making its galleries of oviposition in any elm trees felled 

 during the previous winter, and usually in such numbers as to ensure 

 the destruction of the bark ; 1 do not remember to have seen it in 

 timber smaller than 8 in. diameter. The female makes her way along 

 the bottom of some crack in the bark, often by widening it for some 

 distance, before commencing to burrow, so that the real opening of the 

 gallery is some distance from where the little heap of outturned frass 

 lies which marks its orifice. 



" The male is present for only a brief interval, viz. after the burrow is 

 well commenced, but before any eggs are laid. The burrow is usually 

 about three inches long (very rarely five inches), almost always close to 

 the wood and slightly encroaching on it. Its construction occupies 

 about three weeks. The eggs are laid along either side close to the bark, 

 the cavities in which they lie being somewhat irregular, not nicely fitting 

 the egg as with Hylesinus. The eggs in a burrow number about 100, 

 but I have met with more than 160 in one. They are covered by a 

 rather thick continuous layer of frass, which also lines the floor of the 

 burrow, and extends partially into the roof. 



" The young larvai, starting at right angles to the parent gallery, 

 which is parallel with the axis of the tree, form a very regular ' typo- 

 graph,' at least in those somewhat rare instances in which contiguous 



