THE CANADIAN ENTOMOLOGIST. 



43 



brighter in color as it matures. The head is black, and there is a ring 

 of the same color on the second segment. There are also two rows of 

 black spots along each side. 



The perfect beetle is of a yellowish cream color, with ten black lines 

 or stripes, running lengthways, and a few black dots on the head and 

 thorax. There are three broods of this insect during each year, the last 

 of which remains in the ground during the winter. Some idea of its 

 enormous rate of increase may be gathered from the fact that each female 

 deposits from 700 to 1000 eggs, and that these attain to the perfect beetle 

 state within fifty days, so that the results from a single pair, if allowed to 

 increase without molestation, would, in one season, amount to over fifty 

 millions. The insect, in its several forms of egg, larva and perfect beetle, 

 may frequently be found in company on the same potato vine. 



ITS NATURAL FOOD. 



This insect was originally confined to a comparatively small extent of 

 country, in the region of the Rocky Mountains, where it fed on a species 

 of wild potato, Solatium rostratum ; but having suddenly acquired a taste 

 for the cultivated potato, and adopting that as its principal food, it has 

 gradually spread eastward, until it has invaded our shores. It feeds also 

 readily on many other plants belonging to the order So/anacecE, which in- 

 cludes the tomato and egg-plant as well as the potato — all of interest to 

 the agriculturist — as well as many species of wild plants, such as Black 

 "Henbane, Hyosciamus niger } and Thorn-apple, Datura Stramonium. 



no. 



THE THREE-LINED POTATO BEETLE. 



FIG. 



The Colorado, or ten- 

 lined beetle, must not be 

 confounded with the small- 

 er t/iree-\med potato beetle, 

 Lcma trilineata — Oliv. See 



colors— Pale figure 2 — which has been 



yellow t t black. , , , 



common throughout Cana- 

 da for many years past, and is, at the 

 present time, unusually abundant in 

 some districts, especially in the neigh- Colors— Dull white. 



bourhood of Kincardine. The larva of this beetle (see fig. 3) is smaller, 

 and may be readily distinguished by its disgusting habit of carrying its 

 excrement on its back. 



