8 BULLETIN NO. 8, DIVISION OF ENTOMOLOGY. 



stiff connection, for the reasons set forth, may be overcome when in the 

 cotton-field. 



The late Dr. James S. Bailey,* of Albany, E". Y., was commissioned 

 some time ago to prepare a full account for publication by the Depart- 

 ment of the wood-boriug lepidopterous larvae of the family Cossidae, as he 

 had given much attention to this group and was familiar with all of the 

 North American species. It was his intention to have prepared such 

 an article, giving particular attention to life-habits. Unfortunately his 

 health from the period of his instructions to his recent death was such 

 that he was unable to fully carry out the plau, and we furnish the re- 

 port incomplete and falling short of what it would have been had he 

 lived. We publish it as it was written, and do not desire to be held re- 

 sponsible for his views. The principal species discussed, Cossus center - 

 ensis, was first described by Mr. J. A. Lintuer in the Canadian Ento- 

 mologist for July, 1877, where many of the facts were given that were 

 detailed by Dr. Bailey in a later article in the same periodical for Jan- 

 uary, 1879, and in the report here published. 



This Bulletin concludes with a report by Dr. William McMurtrie, pro- 

 fessor of chemistry in the Illinois State Industrial University, upon 

 certain measurements and tests made by him at our request to deter- 

 mine the relative fineness and strength of the fibre of samples of raw 

 silk raised at the Department. A noticeable result of these experi- 

 ments, as may be seen by reference to the accompanying tables, is 

 that the fibre from worms fed exclusively upon Osage orange is shown 

 to be somewhat finer, and, on the average, equal in strength to that 

 obtained from the mulberry-fed individuals. We also give a plate from 

 photographs taken by Dr. McMurtrie. illustrating the dual nature of 

 the fibre. 



C. Y. E. 



* Dr. Bailey died July 1, 1883. 



