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return home, found that a similar article was manufactured at Liverpool, and sold 

 under the name of "Copland's Rectified Borneote of Petroline;" this he had found 

 equally as useful as the French preparation for extracting grease, and exhibited a 

 number of Lepidoptera and Coleoptera which he had so cleaned : the highly volatile 

 nature of these preparations is said to give them an advantage over camphiue for this 

 purpose, in not requiring the specimens to be subsequently placed in magnesia or 

 other absorbent powder. 



Dr. Power exhibited specimens of Notiophilus rufipes, which species he had 

 recently taken at Shirley, near Croydon, also near Gravesend, and at Cowley, near 

 Uxbridge : he also exhibited an opaque female of Hydroporus picipes ; in this species 

 both sexes are usually glabrous. 



The Rev. Hamlet Clark exhibited a new British species of Hydroporus, recently 

 detected by him in the collection of Mr. VVaterhouse. 



Mr. Stevens exhibited a box of Coleoptera recently received from Mr. Wallace, at 

 Borneo, containing many new and fine species, especially amongst the Longicorns. 



Mr. Newman read the following notes, exhibiting the insects to which reference is 

 made : — 



Silk-spinninj Acarus of the Furze, ^r. 



" I beg to exhibit a mass of silk spun by a minute Acarus, and obligingly handed 

 me, together with multitudes of the little specimens, by Dr. Miluer Barry, of Tunbrid"'e 

 Wells, who writes as follows : — ' When strolling across Rusthall Common this after- 

 noon I noticed some red powder lying in thick cobwebs entangled in the furze: I took 

 up some of the powder, and found it was living and moving, and consisted of myriads 

 of vivacious red insects resembling Acari.' When the mass reached my hands it was 

 of the size and shape of a sparrow's egg, the Acari running over it in all directions, 

 and each adding to the bulk by leaving behind him a continuous thread of the finest 

 conceivable silk. T subsequently sent the mass to Mr. Meade, the Arachnologist, who 

 has carefully examined it, and kindly sent me the following information: — 'The 

 minute animals inhabiting the curious cocoon you sent me are Acari, belonging to the 

 genus Tetranychus of Dufour, the type of which is the little red spider so injurious to 

 plants in hot-houses and rooms, the Aoarus telarius of Linnaeus : most of the species 

 live in society, on plants, and possess the power of forming webs: Koch says, when 

 speaking of an allied species, Tetranychus socius, ' It appears in certain years in such 

 numbers that it covers the trunks and the branches of the lime-trees which it frequents, 

 with such a thick web that they look as if clothed with glazed satin.' I cannot find 

 any description of the species sent by you, although it is closely allied to the common 

 Tetranychus telarius, and I never before saw or found anything like the curious nest 

 which it inhabits.' Since the receipt of Mr. Meade's note I have paid some little 

 attention to the Tetranychus telarius, and find that the net-work of infinitely minute 

 silken threads is admirably adapted to its singularly formed feet, and these are equally 

 well adapted to the office of holdiug on while it perforates the cuticle of the leaf with 

 its rostrum : its hold is so secure that no amount of washing by means of a garden- 

 engine seems to have the eff"ect of removing it: as I have no doubt whatever that these 

 little creatures are exclusively vegetable-feeders, the web cannot serve, as in spiders, 

 the purpose of securing prey, and it is, moreover, never accompanied by the glutinous 

 particles which render the web of spiders so adhesive : as a matter of course, if the 



