XI. INSTRUCTION. 825 



and of the pumps (c, c,) is effected by the mechanism L, which is worked 

 either by a man or by a small water wheel. (The other signs on this drawing 

 IV. correspond with those of the drawings I., II., III.) 



The smaller apparatus is used for experiments with poultry, rabbits, and 

 other small animals. 



3822. Photographs of Microscopic Objects. Enlarged 

 from negatives by Dr. Moddox, for illustration by means of the 

 lantern. James How fy Co. 



3823. Mounted' Preparation to show a method of putting 

 up dried membranous specimens for museums. 



Professor Struthcrs, Aberdeen University. 



The glass jar is not essential. The wire loop displays and also protects 

 the preparation, and the tube enables it to be turned round on the stand, 

 or to be taken out and held up by the stem for demonstration. Curators of 

 museums may remove the cover and examine the mounting. The specimen 

 is a preparation of the human pyloric " valve." 



3823a. Specimens of Linnseus's MS. 



" Iter Dalekarlicum." a MS. journal of a tour made at the suggestion of 

 Governor Reuterholm. in the year 1734, through the provinces of East and 

 West Dalecarlia, by Liuna?us himself, accompanied by several students from 

 the University of Upsala, who were devoted to the study of natural history, 

 each student undertaking to record daily his observations on the particular 

 branch assigned to him. 



The journal, which is chiefly in Swedish, and does not sefem ever to have 

 been published, is illustrated by pen and ink sketches, and accompanied by 

 one engraved and two MS. maps, of the district traversed. 



SPECIMENS FKOM LINN^EUS'S COLLECTIONS. 



a. Zoological. 

 1. My a margaritifera. 



In his letter to Hallet, dated Upsal, Sept. 13, 1748, Linnscus writes, "At 

 " length I have ascertained the manner in which pearls originate and grow 

 " in shells,* and I am able to produce, in any mother-o'-pearl shell that 

 " can be held in the hand, in the course of five or six years, a pearl as large 

 " as the seed of common vetch." 



2. Testudo pusilla, L., native of the Cape of Good Hope, both 

 named in Linnaeus's own hand. 



3. Scomber Chrysurus, native of Carolina. 



* " For this discovery the illustrious author was splendidly rewarded by 

 " the States of the Kingdom." Hallcr. Specimens of pearls so produced 

 by art ill the Mya maryaritifera are in the Linnacan Cabinet. 



44 The shell appears to have been pierced by flexible wires, the ends of 

 "" which perhaps remain therein." (Smith's Selection of the Correspondence 

 of Linnaeus, II , p. 428.) 



In his Memoir of Linnaeus, in Rees's Cyclopaedia, Sir James Smith, after 

 mentioning that his patent of nobility was confirmed by the Diet in 1762, goes 

 on to state that that august body honoured him with a still more solid reward, 

 upwards of 520/. sterling, for his discovery of the art of producing pearls in 

 the river mussel by wounding the shells ; but the practice does not seem to 

 have been prosecuted to any great extent. 



