3<5o 



THE GUIDE TO NATURE 



pulchella, Mull. The members of the 

 genus are all about this size, and are 

 found in every part of the world. There 

 is a little difference in the species. 

 This form, pulchella, has been found in 

 nearly all the continents. In the Rock- 

 ies is a variety called costata, which is 

 beautifully ribbed, and there are two 

 or three other forms in the mountains 

 of the southwestern part of the United 

 States. 



"The habit of this chap is to live in 

 the grass. Doubtless there was some 

 local condition which set them to 

 crawling- about, and they swarmed 

 over the sidewalks. The same condi- 

 tion has often happened. Sometimes 

 on a board that has lain in the back 

 yard near the grass, you will find them 

 in abundance. One collector wrote to 

 me a while ago that under one board 

 he found nearly two thousand speci- 

 mens when the conditions were favor- 

 able. At other times you will not find 

 any in the same locality. The supposi- 

 tion is that they lay a large number of 

 eg"gs and develop into full grown in- 

 dividuals in a comparatively few 

 weeks." 



Studies of the "Oyster-Shell" Scale. 



Cambridge, Massachusetts. 

 To the AA : 



At Winchester, Massachusetts, Ave 

 Avere on the edge of the Middlesex 



Fells, a part of the state of Massa- 

 chusetts Parks Reservation. We were 

 unable to enjoy ourselves in the woods 

 as we had anticipated because the 

 foliage was heavily sprayed with poi- 

 son to destroy the brown tail and 

 gypsy moths . We. however found 

 many butterflies and moths. We 

 sketched from nature and studied the 

 elements of chemistry and otherwise 

 improved the time. 



I send you by mail in separate en- 

 closure a piece of wood which I cut 

 from a tree which is infected with a 

 scale. Kindly give me the name of 

 this scale and refer to some publication 

 from which we can learn its life his- 

 tory. 



James Edwin Mellen, 

 Corresponding Secretary Mellen Chap- 

 ter. 



The specimens of bark which you 

 sent with your letter were infested with 

 the oyster-shell scale (Mytilaspis pom- 

 orum). The oyster-shell scale is one 

 of the most widespread orchard pests 

 in America, and attacks also a great 

 varietv of ornamental plants and 

 shrubs. An amplication of the lime- 

 sulphur wash just before the buds swell 

 is very effective against this insect. It 

 does not destroy the eggs beneath the 

 old scales, but seems to be very effec- 

 tive in killing the young when they 

 emerge in soring" or earlv summer. — - 



THE "OYSTER-SHELL" SCALE INSECT. 



