96 THE BEPORT OF THE No. 36 



that and the following year. In the fall the rhubarb was all taken up and the 

 ground plowed and well cultivated. In 1916 it was planted to cabbage and 

 cauliflowers. In 1917 there was no further appearance of the pest though the 

 land was planted out to potatoes. 



During the past summer more complaints reached the office regarding this 

 insect than any other one pest. Never a mail arrived during its active season, 

 that did not bring letters of specimens. 



Frequent mention was made in the press regarding this " new potato bug " 

 and accounts of its ravages, often exaggerated, gained wide circulation. 



We did not have an opportunity of making any detailed study of the insect, 

 but were able to secure the general outlines of its life history and to observe 

 its injuries. The eggs are laid by the female moth during the latter part of 

 August and in September. They are doubtless laid on various weeds, but we 

 have only found them on couch grass (Agropyrmn repens) where they are very 

 difficult to detect. They are laid loosely and frequently in rather large numbers, 

 attached to the stem, generally being partially surrounded by the leaf sheath. 

 The eggs, which do not appear to have been noted by other workers, are a little 

 less than one millimeter in diameter, circular in outline, faintly ribbed and 

 slightly tinged with pink. 



The larvfe emerge in June and bore a tiny entrance hole in the stem through 

 the centre of which they bore, causing it to Avilt and die. In the rhubarb they 

 frequently bore through and through the crown of the plant, but in potatoes 

 and corn they confine their attention to the stalk. The injury continues through 

 the latter part of July and into the early part of August, when the insect trans- 

 forms to a pupa, to emerge late in August or in September, as an adult moth. 



The unusually severe outbreak of this pest during the past year may have 

 been partly due to the great increase in the number of back yard gardens, fre- 

 quently planted in situations that had formerly been badly overgrown with weeds 

 that would be likely to harbor the pest. The clean cultivation of the plantation 

 during the oviposition period is an obvious step to take. In a permanent planta- 

 tion, such as rhubarb, this is particularly necessary and in land that is planted con- 

 tinuously in garden crops. Gardens should not be planted on waste land that 

 has been allowed to grow to weeds in previous seasons. Whenever possible such 

 land should be thoroughly plowed and cultivated the previous fall in order to 

 destroy as many eggs as possible. As the insect is chiefly a garden pest, picking 

 the injured stalks and destroving the caterpillars is practicable and should be 

 done to prevent outbreaks in future seasons. It is obviously impossible to attack 

 .the insects by means of insecticides. 



The Zebra Caterpillar {Ceramica picta Harr.) 



Unlike the former species, this is a native insect and occurs intermittently 

 over a wide range in the United States and Canada. I have been able to locate 

 about forty-five references to the M-ork of the insect in American literature, 

 consisting for the most part, of brief notes indicating that the pest is not con- 

 sidered to be one of major importance. Neither Chittenden or Sanderson men- 

 tion it in their text books. O'Kane gives it a few lines stating that it feeds on 

 garden crops of various sorts, especially beets, spinach, celery and peas. 



It is apparent from the references to the insect in entomological literature 

 that, while it cannot be considered an unusual pest, serious outbreaks are a 

 somewhat rare occurrence, at least such outbreaks as have been experienced in the 

 Annapolis Valley during the past two years. 



