108 HYDROCAMPA stagnata. 



segment light brown, body pale greyish-brown, the 

 internal vessel rather deeper greyish-brown, broad at 

 the beginning of the third segment, and not visible 

 beyond the ninth, the second segment clear and 

 transparent as the others. 



In another month's time it is nearly half an inch 

 long, of a light brownish-olive colour, the segmental 

 folds of skin and its outline showing the most colour, 

 and also the fine tracheal thread ; the lobes of the 

 head are outlined with darker brown, and the mouth 

 is darker, the ocelli black. When about to hibernate, 

 the body becomes transparent and colourless. 



The full-grown larva measures seven-eighths of an 

 inch in length, is of rather slender proportion, taper- 

 ing from the third segment to the head, and again 

 gradually from about the tenth to the anal extremity ; 

 the head is small, flattened, and tapering towards the 

 mouth ; the segmental divisions and subdivisions are 

 moderately well defined, the skin puckered a little and 

 dimpled along the sides ; the ventral and anal legs 

 fairly well developed, each foot being furnished with a 

 complete circlet of fine hooks ; in colour the head is 

 pale translucent brown, the lobes margined with a 

 reticulation of darker brown, and a similar streak in 

 the middle of each ; the mouth is blackish-brown — 

 sometimes there is a spot of this dark colour on the 

 triangular space above it ; the ocelli are large and 

 black ; the second segment, yellow or olive-yellow, 

 has sometimes a few brown freckles, and a thin trans- 

 verse streak of brown at the hind margin, and a few 

 fainter freckles on each side the dorsal region ; all the 

 rest of the body is of a bright, deep yellow, or else of 

 olive-yellow, but so translucent as to show very dis- 

 tinctly through the skin, not only the broad and 

 blackish-olive internal vessel sliding to and fro, but 

 also the paler trachea, with its larger branches, and 

 the multitude of excessively fine ramifications. In the 

 more olive tinged examples there occur two parallel 

 brown streaks low on the sides of the second, third, 



