580 proceedings: biologicai^ society 



Regular Program 



F. L. Scribner: The lure of Rock Creek Park. 



A brief history of the development of Rock Creek Park was given 

 and its main geographical features described. Then a very extended 

 series of colored lantern sUdes was shown, making a tour of the park. 

 Many general views were shown of the roads, bridges, and plant asso- 

 ciations, in different seasons, and also portraits of some of the indi- 

 vidual blossoms or clusters. 



Mr. Scribner's paper was discussed by Prof. A. S. Hitchcock, Dr. 

 R. W. ShufeIvDT, and Dr. M. B. WaiTE. In response to a question, 

 Mr. Scribner said that some of the pictures referred to as showing 

 extreme detail were taken by a miniature focusing camera, whose 

 plates were about one and one-half inches in length. 



Thomas E. Snyder: The lead cable borer. 



With but few exceptions injury to metal by insects is accidental ; the 

 metal blocks the emergence of an adult or is in the path of a burrowing 

 larva. Lead is the metal most commonly injured but tin, zinc, quick- 

 silver, etc., are also damaged. Bullets, roofing, piping and lining of 

 tanks are some of the large variety of products damaged. 



One of the most serious cases of direct injury to metal by insects is 

 that done to tubular lead telephone fuses by the beetle Dermestes 

 vulpinns Fab. The purpose of the fuse is to protect apparatus from 

 high currents; it melts or "blows" and "grounds" the high current. 

 By eating through the lead (alloy) tape of the fuses, the insects neces- 

 sitate replacement, as if blown out. 



A much more extensive and serious type of injury is that caused to 

 the lead sheathing of aerial telephone cables in California by the beetle 

 Scobicia declivis Lee. This beetle normally breeds in recently felled 

 cord wood piled for fuel, "powder posting" the wood. Another abnor- 

 mal habit is to bore through the staves of wine casks. This beetle 

 attacks the cable in the summer where it lies in contact with the metal 

 suspension ring, which affords it a leverage in boring. The hole allows 

 moisture to penetrate the insulation and numerous widely, separated 

 "short circuits" are caused all at once during the fall rains. A high 

 percentage of "wire trouble" is caused by this beetle. 



No remedy has as yet been found. Chemical repellants, various 

 different types of suspension rings and hard tin and antimony alloys 

 have proved ineffective. Infested cordwood should be burned before 

 the middle of April. {Author's abstract.) 



Mr. Snyder's paper was discussed by Dr. L. O. Howard. 



610TH MEETING 

 The 6ioth regular meeting was held in the lecture hall of the Cosmos 

 Club, April 3, 1920, at 8 p.m. President Hopkins called the meeting 

 to order with forty-two persons present. The minutes of the 609th 

 meeting were read and approved. Upon recommendation of the Coun- 

 cil, Mr. Emerson Stringham of the U. S. Patent Office was elected to 

 membership. 



