470 Insects "which feed upon the Wood of Trees. 



Ciassification. Linnaean order, Coledptera. Groups of other systematists : 

 Mandibulata, Pentamera, ilfelolonthidse Leach. Natural order in Newman's 

 system; iucanites in the Eiitomological Magazine, vol. ii. p. 416. 



Etymology. Dorcus is derived from dorkos, a stag : the mandibles of the 

 male have a similarity to the antlers of a stag^ the name Stag Beetle includes 

 the same idea. Parallelopipedus, one may suppose, implies that the imago's 

 form is that of a parallelopiped. 



Sinodendron is from sino, to injure, and dendron, a tree ; in expression of 

 the supposed case that this S. cylindricum preys upon healthy trees, to the 

 injury of them. Cylindricum, in expression of the form of the imago. 



Facts on the Habits oftlie Larva arid Imago o/Dorctis parallelopipedus, and of 

 those of Sinodendron cylindricum. The Rev. W. T. Bree, M. A., Allesley Rectory, 

 near Coventry, Warwickshire, has, in a contribution of his to the Magazine 

 of Natural History, published in vol. vi. p. 327 — 335. of that work, commu- 

 nicated information to the following amount on this subject: — A living aged 

 ash tree, standing on his premises, was blown down on Dec. 3. 1832. Its trunk, 

 for about 18 ft. up from the part that had been level with the ground, was 

 hollow and decayed at the centre, and afforded some twenty or thirty good 

 barrow-loads of rotten wood. Throughout this carious portion of the tree 

 there occurred numerous individuals, both larvas and imagoes, of the Z)6rcus 

 parallelopipedus, and of its usual associate, Sinodendron cylindricum ; but 

 not a single pupa was discovered : they had perforated it in all directions. 

 Many were found pursuing their occupations in the decayed timber at the 

 distance of 18 ft. from the ground ; " to which height they must have worked 

 their way from the bottom." Z)6rcus parallelopipedus and Sinodendron 

 cylindricum are usual inhabitants of the interior of decayed ash trees, dwelling 

 together promiscuously, and, as it seems, in perfect harmony. Mr. Bree was 

 satisfied that they do not commit any " injury on the living or sound wood ; 

 attacking such only as they find far gone in a state of decay." 



2)6rcus parallelopipedus. 



Egg. Not any fact is in possession, or within reach, for adducing in relation 

 to the egg. 



Larva, (fig. 77. c.) Information on the larva is given above, under " Facts," 

 &c. Mr. Bree has communicated farther, that " The larva of the jDorcus, it 

 strikes me, is very large in proportion to the beetle which is produced from 

 it ; being nearly equal in size to the cockchafer grub, which it very much 

 resembles, except that, instead of being, like that, of a cream colour, it is 

 rather of a bluer white." I suppose that the two insects in the larva state, 

 which Mr. Rivers has supplied, may be of this species, but I doubt about it. 

 I conclude that they were not of the Cossus Ligniperda, because not any of 

 the kind of odour so notable in this species escaped from them. To the 

 species of which they are, whatever this is, and to the history of the larva 

 state of it, belong facts to be found stated in Mr. Rivers's communication 

 and those which I have stated in p. 463., on the condition of the log of pear tree 

 wood. The only conclusive means of discovering the species is, by ascer- 

 taining the characteristics of the imago that is developed from the larva : both 

 the living larvas that Mr. Rivers had supplied have escaped. Each of them 

 was a little longer and stouter than the figure c ; but that figure was delineated 

 from a dead individual, sent to the draughtsman in spirits of wine ; and, as it 

 is probable that it was put into the spirits when alive, it might contract in the 

 dying ; and there is not means of ascertaining that it and the two larvas had 

 been of equal age and growth. If the larvas supplied by Mr. Rivers were of 

 this species, it is right to state that the wood of the log of pear tree wood did 

 not seem "far gone in a state of decay," but dead, dry, and hard. 



Pupa. It seems inferable from the " Facts," &c., above, that December 

 is not an eligible time in which to seek the pupa. 



Imago. (J?g. 77. ; a, malej b, female.) In the " Facts," &c., above, is in- 

 formation on this. It " may be obtained in June and July, in the neighbour- 

 hood of willows." (Samouelle's Enlomologisf s Useful Compendium.^ It is not 



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