BY WALTER W. FROGGATT. 669 



when they descend from their resting-place, thev wander about 

 over the grass for several days before thf^v finally select a place 

 in which to pupate, generally the softer soil against a tree trunk. 

 Into this they burrow to a depth of three or foui- inches, mass- 

 ing their large, oval cocoons in rows, one against the other I 

 watched several large swarms feeding upon the Peppermint-gums 

 { Encalyptnii novce-angliff') at our Experiment .Station at Uralla, 

 and afterwards in their erratic wanderings over the grass; and 

 marked down their final resting place and dug up the cocoons. 

 At Binalong, in April, I observed two large swarms marching in 

 massed formation : the heads of the hind rows always rested 

 upon those in front as they moved along steadily together. 

 Every now and then, the front rank came to a dead stop, when 

 they all rested for three or four minutes; then a number began 

 raising up and tapping down the tip of the abdomen, whereupon 

 the whole band took up the motion: the leading ranks made a 

 fresh start, and all moved along again. In the largest band, T 

 counted two hundred and tifty caterpillars 



Larvfe that pupated in the soil in the middle of April, pro- 

 duced the perfect sawflies in the Insectarium in the early part 

 of October. 



The pupation of this sawfly is very remarkable. Under natural 

 conditions, the long, oval cocoons are formed one above the other 

 into a solid mass like honeycomb. When the full-fed hawse are 

 placed in a jar of sawdust, each forms a separate oval cocoon up 

 to ]J inches in length and J inch in diameter. The walls 

 are very thin, composed of a tough, sticky, papier-mache-like 

 material, the inner surface smooth and black, with the anterior 

 end rounded, and the apical cut off from a false end (containing 

 the cast larval skin loosely attached to the true cocoonj by a 

 slightly convex partition or cap of a greyish-brown colour, except 

 for the black centre just behind the head of the semipupa: the 

 outer side of this cap is fiat, black, and thickly impressed like 

 the surface of a thimble. 



The first moult leaves a very wrinkled, pink and yellow, naked 

 pupa, with all the outlines of the larva, and the abdominal seg- 

 ments curled in underneath the hindlegs. This stage may 



