13 



THE TUSSOCK MOTHS. 



There are three different species of Tussock Moths in Massachu- 

 setts, the first of which is the most common and is known as the 

 White-marked Tussock-moth {Org>/ia leucostigma, A. and S.)- This 

 insect is a native of this country and was figured and described by 

 Abbot and Smith in 1797. Since that time it has received the 

 attention of nearly all of our entomologists. 



The eggs of this species, laid on the cocoon of a female attached 

 to a twig of tulip-tree, was brought to the Insectary, April 22. 1891. 

 They were arranged in an irregular cluster containing about 22,5 in 

 number and were covered by a white, glistening, frothy substance. 

 The eggs are globular with a slight depression on the top, about one 

 twenty-fifth of an inch in diameter and are yellowish white with a 

 pale brown spot on the top and a ring of the same color around it. 



11. White-Marked Tussock- Moth. 



Full grown caterpillar.— After Riley. 



These eggs hatched May 10, and the caterpillars passed their 

 molts (the description of which is omitted here) and reached maturity 

 June 15. The full grown caterpillars. Fig. 11, are about an inch 

 and an eighth in length, of a bright yellow color, si)aringly clothed 

 with long, fine yellow hairs on the sides of the body, and having 

 four short, thick, brush-like, yellowish tufts on the top of the fifth 

 and the three following segments, two long black plumes or pencils 

 extending forward from the sides of the second segment, and a single 

 plume on the top of the twelfth segment. The head and top of the 

 second segment and also two retractile tubercles on the top of the 

 tenth and eleventh segments are bright red ; there is a narrow black 

 or brownish stripe along the top of the back and a wider dusky stripe 

 on each side of the body. 



