2Q2 Mr, Clark' j Obfervations en the Genus Oejlrus. 



When young the larva is fmooth, white, and tranfparent : as it 

 enlarges it becomes browner, and about the time it is full grown it 

 is totally of a deep-brown colour, having numerous dots on its 

 fur face, difpofed in tranfverfe interrupted lines, palling round the 

 fegments. Two diftinct and different kinds of lines are feen on 

 each fegment: the uppermoft of them is narrower, and confifts of 

 lamer dots. Underneath this is a broader line, and the dots con- 

 fiderably fi mailer. The firft are eafily feen, by ufing the lens, to be 

 hooks bent upwards, or towards the tail of the infect. See fig. i, a. 



On examining the broader line of fmall dots (fig. i, b) with a 

 tolerably powerful magnifier, they are alfo found to be hooks, but 

 turned in an oppofite direction, that is, downwards in the abfeefs, 

 and towards the head of the infect. 



Thefe hooks, it is probable, are occafionally erected by the mufcles 

 of the fkin, and according to the feries of them ufed by the larva, it 

 is raifed or depreffed in the abfeefs ; and by this motion, and the 

 confequent irritation, a more or lefs copious fecretion of pus is oc- 

 cafioned for the fuftenance of the larva. 



This lingular arrangement of hooks round the body of the 

 larva, in this inflance ferves the fame purpofe as the legs in other 

 larva:, enabling it to move about in the abfeefs, and to crawl out of 

 it when ripe, and renders the ufe of the tentacula obfervable in the 

 other fpecies not neceffary in this. 



Befide thefe on the fur face of the fkin, there are a number of 

 rounded unarmed prominent points, which have a minute depref- 

 fion in the centre, and appear to be the fpiracula?, being the external 

 opening of the extreme branches of the air tubes. 



In what manner the pus is received by the larva for nourifhment 

 is not immediately difcoverable. In the upper part of the larva, or 

 that end which is applied to the external opening in the fkin, may 



be 



