101. L October. 



After watching it some time, I took it in my hand and stripped 

 off the case o£ duckweed leaf by leaf, leaving the larra naked and 

 perfectly dry ; then placing it in a small dry saucer, I found it much 

 less helpless than I at first thought, for, recovering in a few seconds 

 from the surprise of its novel situation, it began to crawl about and 

 up the side of the saucer ; I then put in a small quantity of water, 

 and placed the larva on it, when it floated without sinking even its 

 feet, and when touched, slid quite helplessly about ; — in fact, I found 

 it now impossible to immerse the larva, for its specific gravity seemed 

 as nothing in comparison with the water. 



After figuring the naked larva, I placed it in a glass of water with 

 a little duckweed on the surface, and then it at once began to spin 

 some of the leaves together with its anterior legs, placing and holding 

 them suitably for its purpose ; and still it remained all the while per- 

 fectly dry, its skin being the very perfection of waterproof texture. 



In the course of six minutes, it had roughly constructed a new 

 case, and was almost hidden from view, by this time lying on its back 

 and employed seemingly in finishing the interior. 



"While out of its case, I found it was three-eighths of an inch long, 

 of slender proportion, thickest in the middle, the anal flap rounded 

 above like a small knob, the colour of the head and second segment 

 black above, and shining, the rest of the body without gloss and of a 

 sooty velvety blackness, but a blacker dorsal line could be distinguished ; 

 a faint olive tint seemed to show through the sooty surface along the 

 spiracular region under a lens, but even that aid did not enable me at 

 this early stage to see the spiracles. 



At the approach of winter, all the larvjo ceased to feed on tlie 

 duckweed, and shut themselves up in their cases for hibernation from 

 eai-ly in December to the beginning of March, 1875, when, during the 

 occurrence of a few mild days, they began to move about and protrude 

 their front segments, but soon retired again until the middle of April ; 

 thenceforward they frequently cnme partly out, and appeared to be 

 feeding well, and, by May 5th, their cases were enlarged with additions 

 from the fresh weed. 



On the 10th of May, T saw, with some anxiety, a larva out of its 

 case, apparently dead at the bottom of the water ; when taken out for 

 examination, it proved to be still alive, but in hopeless plight, infested 

 with extremely minute, slender, whitish, semi-translucent, parasitic 

 worms, which, on emerging, coiled and wriggled round their dying 

 victim. Three other larvic succumbed to th^se parasites soon-afterwards. 



