598 ' PHILOSOPHICAL TRANSACTIONS. [anNO I67I. 



tions discovered divers truths ; among which he deHvers one, commended both 

 for its newness and usefuhiess, which is, to contract the longest tubes, with- 

 out at all prejudicing their perfection, by magnifying so much the angle of 

 vision, that the longest tube shall not perform the like, the lateral rays being 

 so accurately secluded, that more of them shall trouble any of the longest 

 tubes, than those short ones of his contrivance. 



An Observation concer?ii??g certain Insect Husks of the Kcrmes Kind. 

 Communicated hy Mr. Lister, May 22, I67I, wJtich came to Hand 

 since the Printing of the former Sheets. N° 71? p- 2165. 



I gave you a short account formerly* of certain matrices or insect husks, of 

 the kermes kind, which I had some years since observed on plum trees. 

 This instant May has afforded me the same observation, and some little im- 

 provement of it. I have observed the same patellae or husks indifferently on 

 vine branches, cherry laurel, plum trees, and the cherry tree. The figure 

 of the husks is round, except where it cleaves to the branch, in size somewhat 

 larger than half a grey pea. These cleave to their branches, as patellas do to 

 rocks ; they are of a very dark chesntit colour, extremely smooth, and shining 

 membrane like. They adhere commonly to the under side of a branch or 

 twig, and thus are best secured against the injuries of the weather, both of too 

 much sun and rain. They are well fastened to the branches single, and some- 

 times many in company. They are seldom found without vermin, as ants, &c. 

 which, I guess, pierce them and prey upon them. If you open one of them, 

 by cutting off dextrously the top of the husk with a rasor, you will find some- 

 times five or more small white maggots of the wasp or bee kind, sharp at both 

 ends. When these are carefully taken out, you will observe the remainder of 

 their provision of meat, and a partition between them and the branch, where 

 what they secrete is reserved. Lastly, if, when you have cleared the husk of 

 maggots, bee meat and excrements, you then rub the empty membrane on 

 white paper, it will copiously tinge the paper with a beautiful purple or murrey. 

 At the date of this, none of the maggots were yet in nympha, so that you can- 

 not expect from me a description of the bee or wasp when they come to per- 

 fection. Few cherry trees, I suppose, in any place, but will yield them some 

 of these berries. 



* March 17, 167O-I. I find in my notes (says he) tliat some years ago I gathered off our Eng- 

 lish oak round worm husks very hke kermes berries, but I then made no trial of them. Again, I 

 have often observed on plum trees and cherry trees, also on the vine and cherry laurel, certain 

 patellae or flat husks containing worms, which (or at least tlie husks, for tliem only I had the op- 

 portunity of making tlie experiment on) will strike a carnation with lye, and stand. 



