COLEOPTERA. 93 



between the bark and the wood, often in great numbers together, 

 and, when they are about to become pupae, each one surrounds 

 itself with an oval ring of woody fibres, within which it undergoes 

 its transformations. The beetle is matured before winter, but 

 does not leave the tree until spring. It is the ribbed Rhagium, 

 or Rhagium Uneatum*, so named because it has three elevated 

 longitudinal lines or ribs on each wing-cover ; and it measures from 

 four and a half to seven tenths of an inch in length. The head 

 and thorax are gray, striped with black, and thickly punctured ; 

 the antennae are about as long as the two forenamed parts of the 

 body together ; the thorax is narrow, cylindrical before and behind, 

 and swelled out in the middle by a large pointed wart or tubercle 

 on each side ; the wing-covers are wide at the shoulders, grad- 

 ually taper behind, and are slightly convex above ; they are 

 coarsely punctured between the smooth elevated lines, and are 

 variegated with reddish ash-color and black, the latter forming 

 two irregular transverse bands ; the under-side of the body, and 

 the legs, are variegated with dull red, gray, and black. The gray 

 portions on this beetle are occasioned by very short hairs, forming 

 a close kind of nap, which is easily rubbed off. 



Mr. Say thought the foregoing to be the only species of Rha- 

 gium in the United States. There is, however, another one, 

 closely allied in form to the willow Rhagium of Europe, which 

 was obtained by Mr. Leonard in Dublin, N. H., and the same 

 insect has been found in other parts of New England. It does 

 not appear to have been described, and is the Rhagium decolora- 

 tum of my Catalogue, so named because the wing-covers appear 

 discolored, as if their original hue had faded away. It is from 

 eight tenths of an inch to one inch, or rather more, in length. It 

 is proportionally longer and narrower than the ribbed Rhagium, 

 and its antennae are two thirds the length of the body ; its wing- 

 covers are smooth or not ribbed, and of a dirty brownish yellow 

 or clay color ; the rest of the body, the legs, and the antennae, 

 are reddish brown. It is possible that this may be only a variety 

 of a species which has blue or blackish wing-covers ; but all the 

 specimens that have fallen under my observation are alike. 



* Stenocorus lineatus of Olivier. 



