200 ENTOMOLOGICAL NEWS. [September, 



With the exception of the Klaeger japanned pins, which are 

 made of steel with a brass head, all of the above are made of 

 brass-wire, either plated or japanned ; the latter, if properly 

 done, prevents corroding, which is a great advantage. 



The writer's own experience goes to show that steel pins may 

 not have as much spring as in some of the hard brass pins, but 

 they are superior in stiffness, and not so liable to clinch on the 

 point. 



As a perusal of the above tables will show considerable varia- 

 bility and uncertainty in the individual grades, and inconsistency 

 in the gradation, I would suggest as a standard the following 

 table of dimensions : 



A uniform length of 38 mm. is suggested for such orders in 

 which the body does not vary to a great extent. In this case 

 the diameters should be the same as in numbers 2, 3, 4, 5, 6 and 

 7 in the above table. 



It is to be hoped that entomologists will become aroused to 

 the advisability of adopting a properly graded standard, and 

 using no other. Manufacturers would no doubt undertake to 

 supply the demand if entomologists can be induced to unite in 

 this movement. 



-o- 



CARNIVOROUS LARVA OF MELANOTUS COMMUNIS. 



By FREDERIC ORMONDE. 



Probably one of the most exhaustive series of experiments 

 relative to the economy, life-history, etc., of the Elateridae ever 

 made in this or any other country, was that of Professors Corn- 

 stock and Slingerland, of the Cornell Experiment Station, the 

 results of which were given to the public in Bulletin 33 of that 



