262 THE CANADIAN NATURALIST. [Aug. 



tli:in fifty individuals, met with on about a mile of road within a 

 short distance of the city. 



Considering their great abundance within their present habitat; 

 and their prospective dissemination over the Province, it is desir- 

 able that information respecting the appearance and habits of these 

 insects should be given to the public, and means devised for their 

 destruction. Farmers and gardeners should kill every caterpillar 

 on their turnips, cabbages, &c., and be provided with nets to cap- 

 ture the perfect insects. The chrysalids should also be sought for 

 on the fences during the fall and winter, and destroyed. Unless 

 these precautions be taken, the injury caused by this butterfly to 

 the green crops in Canada may become very serious. 



The following is a description of the insect : 



Male — wings white, (or light yellow) with one blackish spot on 

 the fore wings above, and two beneath, a black band on the apex 

 on the upper side, extending a short distance along the adjacent 

 marsrins, a black dash on the fore eds-e of the hind win2;s, which 

 are beneath of a pale yellow sprinkled with black. Body black, 

 antennae annulated with black and white. Female has two black- 

 ish spots on upper side of anterior wings. Expands about two 

 inches. 



Chrysalis — Pale green, speckled with black, suspended horizon- 

 tally by the tail and a thread across the middle. 



Caterpillar — About 1 J inches long when full grown, green finely 

 dotted with black, a yellow stripe along the back, and a row of 

 yellow spots along each side in a line with the spiracles. 



The caterpillars reared by me were about one-twelfth of an inch 

 long when I procured them, and attained their full size in eleven 

 days. On the 19th June they became pupae, and seven days after 

 the perfect insects appeared. The butterfly therefore passes 

 throusrh all its chancres in less than a month. Three or four 

 broods are produced during the season. 



(Read before the Quebec Branchy Entomological Society of Canada. *lth 

 July, 1864.) 



SYNOPSIS OF CANADIAN FERNS AND FILICOID 



PLANTS. 



By George Lawson, Ph.D., LL.D. 



The following Synopsis embraces a concise statement of what is 

 known respecting Canadian ferns and filicoid plants. Imperfect 

 as it is, I trust that it will prove useful to botanists and fern 



