SAW-FLIES. 



SAW-FLIES. 



beer by boiling the young shoots of the sassa- 

 fras in water, to which a certain quantity of mo- 

 Jasses or sugar is added, the whole being left to 

 ferment. The beer is regarded as a wholesome 

 and pleasant drink during summer. So is an 

 infusion of the bark of the roots, which is 

 much drunk for the cure of cutaneous and 

 other disorders. 



SAW-FLIES. The names of above 60 

 srpecies of saw-flies, natives of the United 

 States, and found in Massachusetts, are given 

 in Dr. Harris's Catalogue. Some of these are 

 very interesting in their caterpillar state. One 

 of the largest flies is called Cimbex Ulmi, be- 

 cause it inhabits the elm. The female of this 

 species, at first sight, might be mistaken for the 

 hornet. (The name Cimbex was originally 

 given by the Greeks to certain insects resem- 

 bling bees and wasps, but not producing honey.) 

 The elm saw-fly measures an inch in length, 

 the wings expanding about 2 inches. It ap- 

 pears in the Eastern States from the last of 

 May to the middle of June, during which the 

 female lays her eggs upon the common Ameri- 

 can elm, the leaves of which serve as food for 

 the young caterpillars hatched out. These 

 come to their growth in August, and then mea- 

 sure from 1 to 2 inches in length. Like all 

 false caterpillars of the genus Cimbex, this in- 

 sect, when handled or disturbed, betrays its 

 fears or its displeasure by spirting out a watery 

 fluid from certain little pores situated on the 

 sides of its body just above its spiracles. The 

 false caterpillars of other saw-flies prove very 

 destructive to pines and other fir trees. They 

 crawl down the trees and weave cocoons which 

 are concealed in the leaves, &c. In the follow- 

 ing spring the insects burst their chrysalids 

 and come forth as winged flies. 



No means, says Dr. Harris, for the destruc- 

 tion of the caterpillars of the iir saw-fly have 

 been tried here, except showering them with 

 soap-suds, and with solutions of whale-oil 

 soap, which has been found effectual. They 

 may also be shaken off or beaten from the 

 trees, early in the morning, when they are tor- 

 pid and easily fall, and may be collected in 

 sheets, and be burned or given to swine. For 

 other means to check their depredations the 

 reader may consult the articles on the pine and 

 fir saw-flies of Europe, contained in Kollar's 

 Treatise. 



Dr. Harris has described a kind of saw-fly 

 (Selandria vitis), which attacks the grape-vine. 

 It is of a jet-black colour, except the upper 

 part of the thorax, which is red, the legs being 

 a pale-yellow or whitish. The body is about 

 J of an inch long. The false caterpillars pro- 

 ceeding from the eggs of these flies may be 

 found in swarms of various ages on the lower 

 sides of the leaves, some very small and others 

 fully grown. When fully grown they measure 

 about ths of an inch in length. The body is 

 a light-green, the legs and tip of the tail being 

 black. After the first moulting they become 

 almost entirely yellow, and then leave the vine 

 to burrow in the ground. They come out again 

 from their chrysalis state in about a fortnight, 

 pair and lay eggs for a second brood. The 

 young of the second brood are not transformed 

 into flies until the succeeding spring, remain- 

 080 



| ing in the ground in their cocoons through the 

 winter. " For some years previous to the pub- 

 lication of my Discourse," says Dr. Harris, "I 

 I observed that these insects annually increased 

 ! in number, and, in the year 1832, they had be- 

 come so numerous and destructive that many 

 vines were entirely stripped of their leaves by 

 them. Whether the remedies then proposed 

 by me, or any other means, have tended to di- 

 roinish their numbers, or to keep them in check, 

 I have not been able to ascertain, and have 

 had no further opportunity for making observa- 

 tions on the insects themselves. At that time, 

 air-slacked lime, which was found to be fatal 

 to these false caterpillars of the vine, was ad- 

 vised to be dusted upon them, and strewed also 

 upon the ground under the vines, to insure the 

 destruction of such of the insects as might 

 fall. A solution of one pound of common hard 

 soap in five or six gallons of soft water, is used 

 by English gardeners to destroy the young of 

 the gooseberry saw-fly ; and the same was re- 

 commended to be tried upon the insects under 

 consideration. 



" All the young of the saw-flies do not so 

 closely resemble caterpillars as the preceding; 

 some of them, as has already been stated, have 

 the form of slugs or naked snails. Of this de- 

 scription is the kind called the slug-worm in 

 this country, and the slimy grub of the pear 

 tree in Europe. So different are these from, 

 the other false caterpillars, that they would not 

 be suspected to belong to the same family. 

 Their relationship becomes evident, however, 

 when they have finished their transformations; 

 and accordingly we find that the saw-flies of 

 our slug-worms and those of the vine are so 

 much alike in form and structure, that they 

 are both included in the same genus. More- 

 over, there are certain false caterpillars, inter- 

 mediate in their forms and appearance between 

 the slimy and slug like kinds and those that 

 more nearly resemble the true caterpillars; 

 thus admirably illustrating the truth of the re- 

 mark, that nature proceeds not with abrupt or 

 unequal steps ; or, in other words, that amidst 

 the immense variety of living forms, where- 

 with this earth has been peopled, there is a re- 

 gular gradation and connection, which, in par- 

 ticular cases, if we fail to discover, it is rather 

 to be attributed to our own ignorance and 

 short-sightedness, than to any want of harmony 

 and regularity in the plan of the Creator. la 

 considering the resemblances of species, we 

 cannot fail to admire the care that has been 

 taken, by almost insensible shades of differ- 

 ence among them, or by peculiar circum- 

 stances controlling their distribution, their ha- 

 bits of life, and their choice of food, to prevent 

 them from commingling, whereby each species 

 is made to preserve forever its individual 

 identity. 



" The saw-fly of the rose, which, as it does 

 not seem to have been described before, may 

 be called Selandria rora, from its favourite 

 plant, so nearly resembles the slug-worm saw- 

 fly as not to be distinguished therefrom except 

 by a practised observer. The caterpillars of 

 these perform their appointed work of destruc- 

 tion in the autumn ; they then go into the 

 ground, make their earthen cells, remain there- 



