4 The Rev. W. Kirby on an Insect Jet ding on Stone. 



me specimens of the beetles, and also of the asbestos ; the 

 latter appeared to be of the flexible kind, which is called 

 Amianth. Upon examining the former, I find it to be the 

 Dermestes vulpinus Fabr. (Oliv. Ins. No. 9. t. \.J\ 6), a species 

 common to South Europe and South Africa. As the animals 

 of this tribe are not particular in selecting a place in which 

 to undergo their metamorphosis, it is not probable that they 

 would have taken the trouble to perforate the asbestos for that 

 sole purpose, since they will not only assume the pupa in the 

 exuviae of the animal they have devoured, but even under their 

 own excrement (see De Geer, iv. 196): but a further proof 

 that this was not their object, is furnished by the varying size 

 of the holes perforated in the specimen of the Amianth that 

 Mr. Hunneman gave me. There were three, one of which 

 was a line and half in diameter ; another, a line and three- 

 fourths ; and a third, two lines: from whence it seems to fol- 

 low that the insects that perforated it were in different stages 

 of growth ; and consequently derived nutriment from that sub- 

 stance. 



I hope that the fact I have here recorded will not be un- 

 worthy a place in the Philosophical Magazine, and that it 

 may stimulate some of your readers, who may have had an 

 opportunity of making observations on similar subjects, to lay 

 them before the public. Insulated facts, though seemingly 

 trifling, are often of great use to the physiologist and natural 

 philosopher. I am, yours, &c. 



Wm. Kirby. 



II. Thermometrical Experiments in ascertaining the Straigtk 

 of the Sun^s Rays in a keen frosty Day, S)C. 8fc. By Dr. 



W. BURNEY. 



To the Editors of the Philosophical Magazine and Jownal. 



Gosport, Jan. 15, 1823. 

 HPHE bright and unobstructed sunshine today, from twelve 

 -■- till one o'clock p.m., had only a power of Si" over a Fah- 

 renheit's thermometer conveniently placed for the experiment ; 

 the maximum height of the thermometer in the sunshine being 

 33^°, and that of the thermometer in the shade, in a northern ' 

 aspect, 28°. 



It is a curious fac, that during the time of this experiment 

 a good Fahrenheit's thermometer, also placed in the sun's rays, 

 in a cylindrical glass tube nine inches long and one inch dia- 

 meter, (having a brass screw top and an aperture at the bot- 

 tom for the admission of air,) rose 21° higher than a similar 

 thermometer very near it and in the sun's rays, but without 



any 



