74 NEW YORK STATE MUSEUM 



are based on mistaken determinations, and that in reality they belong to a 

 very similar species, M. olyra Hbst. This elm borer was reared b)- us 

 in abundance from American elms growing at Berlin Mass., and in small 

 numbers by Mr M. F. Adams and the writer, from American elms in the 

 vicinity of Buffalo. These insects enter trees very shortly after injury, and 

 there are facts which go far toward showing that occasionally they may 

 attack trees in practically normal condition. It is sometimes very difficult 

 to decide \vhether this species or the elm borer, Saperda trident a ta 

 Oliv., is the primary cause of the death of shade trees. It seems probable 

 that in most cases at least, the elms became sickly before being seriously 

 injured by either insect. 



Distribution. The e.xistence of this species in Canada, Pennsylvania, 

 Georgia and South Dakota, has been recorded by Dr Horn, and the records 

 given above show that it occurs in Mas.sachusetts, New York and New 

 Jersey. This species probably has a somewhat general distribution over 

 the northeastern United States and southeastern Canada. 



Parasites. Several species were reared from trees badly infested by 

 this borer, and smaller numbers of M. armicollis Say and by Sap- 

 e r tl a t r i d e n t a t a ()li\-. The following parasites were in all probability 

 oljtained from this borer: Hrachistes magdalis Cress., Entelus 

 o n e r a t i b'itch, .S m i c r a m i c r o g a s t e r .Say, a pteromalid and a small 

 fly, L i m o s i n a c r a s s i m a n a Hal., all being determined by Messrs 

 Ashmead and Coquillett through the courtesy of Dr Howard. 



Remedial measures. The most effective method of checking the devas- 

 tations of this insect and its allies, is found in cutting the infested limbs 

 and burning them before the appearance of the i)eetles in May. Thorough 

 work along this line will so reduce the numbers of the insect that they will 

 cause very little or no trouble. Prof. Pettit has suggested that in the case 

 of valuable shade trees, it might be well to cut poles of green elm and set 

 them nearby for the purpose of attracting the beetles. These poles should 

 be set the last of May and removed and burned sometime in July, provided 



