THE CAXAIJIAN ENTOMOLOGIST. 



surface shining, sparsely punctured ; antennje about 35-jointed, 3 subequal 

 to 4 + 5 ] head shining, polished, with shallow, widely-separate punctures; 

 a large impunctate spot on the lower inner orbits ; middle fovea deep, 

 spear-shape, with the long point above ; lateral postocellar furrows dis- 

 tinct, converging to the occiput, postocellar area parted by a longitudinal 

 furrow ; anterior lobe of mesonotum and scutel impunctate ; prothorax, 

 lateral lobes of mesonotum and pleurae punctured like vertex ; laterally 

 the pronotum has a large hump ; legs normal ; venation as in /. Kincaidi 

 Roh.; abdomen finely reticulate ; last ventral segment of the abdomen 

 almost as long as wide, the apex gently rounded. Colour reddish-brown ; 

 clypeus, labrum, mandibles, smooth inner orbital area, posterior orbits, 

 four longitudinal lines on vertex, anterior lobe of mesonotum, scutel, part 

 of lateral lobes, pleural and abdomen straw-yellow ; antennae and legs 

 darker than body, partly brown. Wings hyaline, venation brown. 



Type locality : Minn. Collection of W. H. Ashmead. 



Type, No. 12763, U. S. N. M. 



This species is allied to /. brtmnicans (Nort.), but the scape is 

 shorter, the last ventral segment is nearly as long as wide (not half as long 

 as wide as in brunnicans Norl.), the labrum has a long spear-shaped 

 tooth (not broad with the anterior margin triangular, as in brtmnicans), 

 and the colour is lighter. It is not marked with black, as is /. ochrocera 

 (Nort.). 



THE LARCH SAW-FLY ( LYG^ONEMATUS ERICHSONII, 



HARTZ.) IN MINNESOTA. 



BY A. G. RUGGLES, ST. ANTHONY PARK, MINN. 



The Larch Saw-fly has become a very serious pest on the tamaracks 

 in northern Minnesota. Reports of damage from several parts of the 

 State came to the Minnesota Entomologist's office during the fall of 1909. 

 The writer, in July, examined the damage that had been done to the 

 tamaracks in the State preserve of Itasca Park. This park, a primeval 

 forest of fifty square miles, contains within its borders Lake Itasca, the 

 source of the Mississippi. Attention was first attracted to the great 

 amount of timber, dying or dead, in the swamp regions around the shores 

 of the lake. At first it was thought that the trees were being killed by an 

 excess of water, but upon closer examination it was proved beyond a 

 doubt that Z. Erichsonii was the cause. The moss under any of these 

 trees, on being turned over, revealed many thousands of cocoons. Under 

 absolutely dead trees only empty cocoons were found, but under trees 



March, 1910 



