138 THE CANADIAN ENTOMOLOGIST. 



Worm ; LeConte's Pine Worm ; the Colorado Potato Beetle ; the Army 

 Worm ; the Wheat-head Army Worm ; the Rocky Mountain Locust ; the 

 Hellgrammite Fly, and the Yucca Borer. The bulk of the report, sixty- 

 seven pages in all, is occupied with details in reference to that terrible 

 scourge of the West, the Rocky Mountain Locust, Caloptenus spretus. the 

 other and less important subjects being much more briefly treated of. 

 These reports contain an immense fund of valuable information, and have 

 done much to popularize Entomology in America. 



Harpalus caliginosiis from Nature, by Franklin C. Hill ; two plates. 

 We are indebted to Mr. Franklin C. Hill, of Printeton College, N. ]•• for 

 copies of these excellent plates, recently published. They are beautifully 

 finished and conveniently mounted on cards, 5x8, with all the organs and 

 divisions both of the under and upper surface, distinctly named They 

 will prove a valuable help to beginners, and indeed to all who are not 

 already familiar with the names of the different portions of the body of 

 Coleopterous insects. 



CORRESPONDENCE. 



AN INSTANCE OF RETARDED DEVELOPMENT. 



On the 24th of September, 1875, I took a great many large cater- 

 pillars of a reddish buff color, with a dark dorsal stripe, feeding on 

 willow. They soon went down to the soil and spun themselves up in hard 

 brown cocoons, when I put them away for the winter. In the spring of 

 1876 I brought them to the heat, and after waiting some time and nothing 

 appearing, I opened one of them and found the caterpillar alive and as 

 fresh in color as when it first spun up. In this condition they continued 

 until the fall, when I again put them away for the wmter. In the spring 

 of 1877 I again examined them, and found them fresh and with signs of 

 life, but as the season advanced I opened some and found them dead, and 

 the remainder having assumed a shrivelled look, I laid them aside as 

 hopeless. On the 17th of June my attention was attracted by a scratching 

 noise, which I found came from these cocoons, which were now reduced 



