68 COLEOPTERA. 



States is tlie Brenthus (Arrhenodes) septemtrionis * of Herbst 

 (Fig. 34), the Northern Brenthus, so named because most 

 of the other species are tropical insects. It 

 is of a mahogany-brown color ; the wing-cases 

 are somewhat darker, ornamented with nar- 

 row tawny-yellow spots, and marked with deep 

 furrows, the sides of which are punctured ; the 

 thorax is nearly egg-shaped, broadest behind 

 the middle, and highly polished. The com- 

 mon length of this insect, including the snout, is six tenths 

 of an inch ; but much larger as well as smaller specimens 

 frequently occur. The Northern Brenthus inhabits the white 

 oak, on the trunks and under the bark of which it may be 

 found in June and July, having then completed its trans- 

 formations. The female, when about to lay her eggs, punc- 

 tures the bark with her slender snout, and drops an egg in 

 each hole thus made. The grub, as soon as it is hatched, 

 bores into the solid wood, forming a cylindrical passage, 

 which it keeps clear by pushing its castings out of the orifice 

 of the hole, as fast as they accumulate. These castings or 

 chips are like very fine sawdust ; and the holes made by 

 the insects are easily discovered by the dust around them. 

 When fully grown, the grub measures rather more than an 

 inch in length, and not quite one tenth of an inch in thick- 

 ness. It is nearly cylindrical, being only a little flattened 

 on the under-side, and is of a whitish color, except the last 

 segment, which is dark chestnut-brown. Each of the first 

 three segments is provided with a pair of legs, and there 

 is a fleshy prop-leg under the hinder extremity of the body. 

 The last segment is of a horny consistence, and is obliquely 

 hollowed at the end, so as to form a kind of gouge or scoop, 

 the edges of which are furnished with little notches or teeth. 

 It is by means of this singular scoop that the grub shovels 

 the minute grains of the wood out of its burrow. The pupa 



* A mistake undoubtedly for septemtrionalis. It is the Brenthus maxillosus of 

 Olivier and Schonherr. 



