THE OAK-PRUNER. 89 



in April, they were from 4 to 5""" loug. They ate the wood under the bai'k, follow- 

 ing its grain, and packed their burrows solidly with their dust. The growth and 

 progress were both slow, for by the next April they had scarcely more than doubled 

 in length and had not traveled more than from 4 to 6 inches during the year ; but 

 after July they developed an enormous appetite and consumed the wood for at least 

 an inch in length and often entirely around the limb, ejecting their castings through 

 holes made in the bark. When full fed they bore obliquely an oval hole into the 

 wood, penetrating it from 4 to 10 inches. The larva then packs the opening with 

 fine castings and enlarges a coupJe of inches of the interior of the burrow by gnaw- 

 ing off its sides a quantity of coarse fiber, in which it lies, after tux"uing its head to 

 the entrance. When about to become pupa (I witnessed the process) the skin rup- 

 tures on the dorsum of three or four segments next the head ; the head of the pupa 

 appears, and after about half an hour's wriggling the whole body is divested of its 

 covering. To the observer the pupa appears to crawl out of the skin, but in fact the 

 skin with the large mandibles is forced backwards by the alternate extension and con- 

 traction of the segments, assisted materially by the fiber that surrounds it. After 

 its soft body hardens the same movements free it from the fiber, some being shoved 

 in advance of the head, and some posteriorly, the exuvicB being often found at the 

 distal end of the hole. The time spent in the pupal state is indefinite and does not 

 seem to concern greatly the time of the appearance of the beetle. Sticks split open 

 at different periods from December till March contained larvae and pupae about equally, 

 but no developed beetles. A larva that I observed go into the wood in April appeared 

 as a beetle among the first of such as had presumably pupated in the fall. 



The number of these beetles obtained that and the present season was great and 

 afforded a good opportunity to observe individual variations, and they do differ 

 greatly. In length from 8 to 18""" ; in pubescence, some being nearly naked and uui- 

 colored, others having it longer and condensed into spots or almost vittate ; some 

 being quite slender and elongate, while others are short and broad. The surface of 

 the elytra is mostly uniform, but in some, especially such as are narrow and elon- 

 gated, one or two costse are more or less evident. 



Now, although this account differs so widely from that given by Mr. Fitch, still 

 the beetles are the same. Unfortunately, I have never been able to find any pruned 

 oak limbs from which to obtaiu the insects myself, but I have a good set from Mr. 

 Blanchard, of Massachusetts, presumably from the oak, which are identical. Througli 

 the kindness of Mr. F. Clarkson, I have a set of those described by him in the Can. 

 Ent., vol. 17, p. 188, from oak limbs, and which became imagoes in November, and 

 there is no perceptible difference. Dr. George H. Horn says, "They are the same." 

 To identify Elaphidion parallelum had always been a puzzle to me, and I once thought 

 I had a real set ; I obtained it about a dozen times by exchange, but could never be 

 satisfied that the specimens received were not pauperized or peculiar individuals of 

 E. villosum. On comparing my hickory insects with all the descriptions of H. villosum 

 and parallelum and their several synonyms, as far as I possess them, it was easy to 

 pick out sets that would answer satisfactorily all their requirements, and I became 

 satisfied that E. parallelum could not be separated. 



29. Elaphidion parallelum Newman. 

 (Larva, PI. xvii, Fig. 1.) 



This borer, according to Riley, infests the oak, and Mr. Tyler Town- 

 seud, of Washington, D. C, has found it to be the common oak pruner 

 of the vicinity of Constantine, Mich., while it also is common in hickory.* 



* Dr. Horn has, in a letter to Dr. Hamilton (Can. Ent., Aug., 1887), stated that 

 Elaphidion villosum and parallelum "are inseparable." It is, however, too late, since 

 this note is added in the galley proof, to combine the accounts of the latter so-called 

 species with that of E. villosum. 



