360 THE CANADIAN ENTOMOLOGIST. 



said 1 was quite right, and that Mr, Walker, with liis usual carelessness, 

 had got the Contig/ia label on the wrong specimen, and thanked me for 

 calling his attention to the error, which he had corrected. 



At the Annual Meeting of the Ent. Soc. of Ont., 26th and 37th 

 October this year, I saw for the first time the D'Urban collection of moths 

 deposited in November, 1871, in which I found a specimen of Contigua 

 marked Confinis in Walker's handwriting, as confirmed by Dr. Bethune. 

 'I'his shows that Walker had confused his own species of these moths very 

 badly. Henry H. Lyman, Montreal. 



POGONOMVRMEX OCCIDENTALIS. 



On page 351 of this magazine Professor Cockerell notes his observa- 

 tion of the /'(7^^;/£';;/_v;-;«^.t t'raV^^z/rt//^ at Ruleton, within twelve miles of 

 tiie western limit of Kansas, and considers this as the indication of the 

 eastern limit or beginning of the arid region. Our investigations of the 

 range of this large ant in Kansas have shown us that its eastern limit is 

 found far to the east of the point mentioned. The species occurs as far 

 east in this State as the Sixth Principal Meridian, or in the counties of 

 Republic, Ottawa, McPherson and Sedgwick, on a line about two-fifths of 

 the length of the State from the eastern border. One would scarcely be 

 acquainted with climatic conditions in Kansas who should consider this 

 ant as a mark of the " arid region," as west of the line indicated are found 

 some of the best farming lands of the State. Especially is this true of the 

 wlieat lands, as the counties named are among those famous for the pro- 

 duction of this cereal. Notwithstanding its occasional occurrence along 

 the extreme eastern limit above indicated, the favoured home of the species 

 is really within the western hundred miles of the State, and thence west to 

 the mountains, where in specially suitable localities it sometimes occurs in 

 astonishing abundance. From its habit of clearing about its mounds a 

 considerable space of vegetation, this ant is not liked by farmers, and 

 various measures have been taken to destroy it, one of the most successful 

 being the pouring into the centre of the formicary, opened for the purpose, 

 a quantity of carbon bisulphide, the opening being then closed to retain 

 the fumes, which finally penetrate to the depths of the burrows, destroying 

 the inmates. As these cleared spaces sometinies attain the diameter of 

 twenty-four feet, and as the hills may occur a few rods apart, it will be 

 seen that the ant is not a desirable occupant in cultivated fields. How- 

 ever, it is well known that regular cultivation of the soil of infested fields 

 is a great deterrent to their occupation by the Pogonomyrmex, j^erhaps less 

 through the dislodgment of well-established colonies than through the 

 discouragement of new ones. Thus it comes to be true that in fields 

 properly handled the ant ceases to be a general pest, and the {t\v large 

 colonies are readily destroyed by the means above indicated. The species 

 is therefore economically of less importance than is sometimes believed. 



E. A. PoPENOE, Manhattan, Kan. 



Mailed December 12th, i9o<|. 



