r 



778 



REroKT — 1884. 



.J^l 



apparently belong to sense-organs referable to llie same category, and are dis- 

 tributed widely over the surface of the body. The histology of the portions of 

 stin containing these is not dest.ibud. Again, in Exox, similarly scattered sense- 

 organs are met with which, however, Loydig considers to be identical in stnictiue 

 with the beaker-shaped scnso-orgaos or end-buds. 



In one of the commonest North American silurids, Andurus catus, the skin is 

 possessed of numerous small independent sense-organs, which unquestionably bekin<r 

 to the type of * Nervenhiigel ' (nerve-hillock), only they are neither so superficial 

 as tli(; ' free ' nerve-hillocks of other Teleosts, nor included in a groove orcanal like 

 the larger nerve-hillocks met with iu the course of the lateral line, or in the canal- 

 of the head. These structures are small tlask-shaped sacs, occupying the whole 

 thickness of the epidermis, but not ailecting the corium. The superiicial epithelium 

 is continued into the mouth of the sac, which is lined by a cuticular border derived 

 from it, except in ihi' fundus, where a few conical sensory hair-cells are found. 

 These are smTounded 'iv imbricated supporting cells, 'Htiitzzfllen.'Avhich gradually 

 pass into the abo"e-men led superKcial epithelial ci'lls. In the mode of their 

 distribution on th<j head, as well as in their Iristological structure, these sense- 

 organs recall the ' nerve-sacs' of the ganoids, but, instead of being confined tn tht 

 head, they extend over the whole trunk o)i the dorsal and ventraL as well as on the 

 lateral aspects. Whether they have any segmental grouping like the large nerve- 

 hillocks in the lateral canf;l.? must be a matter for future investigatit)n. 



5. On the Function of the Air-hladdvr an<^ its ril'dionshtj} to the Auditorij 

 Organ in Aniiurus. Bij Professor R. Kamsay Wright, M.A., B.Sc. 



The anatom cal features of the parts concerned have been already described in 

 p preliminary communication to the ' Zoologischer Anzeiger,' No, IGl'. The 

 functions of the air-bladder in the liglit of jMoreau's researches were alluded to. 

 and it was suggested that the alterations of pressure incident to change of level in 

 wjiter are communicated to the brain through the auditory nerve. Professor 

 Wright supposes that the air-bladder is also sensitive to sound-waves, and that the 

 same channel of communication with the auditory apparatus serves for the trans- 

 mission of vibrations to the endolymph. In contirmatiou of the latter view 

 Prol'essor Iladdou referred to the more specialised conditions in some tropicr.l 

 siluroids, and to the stridulating apparatus described by him in some of these. 



6. On the Jessop Collection, to illustrate the Forestry of the United States, 

 m the New York Natural History Museum. By Albert S. Bickmore. 



The great importance of the forest industries and lumber trade of the United 

 States led General Walker, the Superintendent of the Tenth Census, to provide for 

 a corps of competent experts, under the direction of Professor Charles S. Sargent, 

 who have made new explorations of our forest lands, and gathered original datit 

 regarding their present extent. The results of these elaborate researches have 

 been partially published from time to time in the fcn-m of bulletins, and the com- 

 pleted work will soon a]»pear in two large quarto volumes of the census series. To 

 place this great fund ot valuable information before the artisan and laboiu'in^ 

 classes in an accessible form, a great collection of our forestry and its products was 

 needed, and this Mr. Morris K. Jessop oflered to provide at his own expense. 

 After the field work planned by the census had been finished. Professor Sargent 

 directed his assistants to return to the forests, and to carefully select the individuallv 

 largest and soundest tree of each species. Professor Sargent is preparing a manual 

 which will be a guide to the collection, and which contains all the most importan: 

 information in the large census volume that will be useful to the visitors and to the 

 artisan classes. The mu.seum is most fortiuiate in its location in Central Park, 

 ■where more native and domesticated species are flouri.shing than can be seen 

 together at any other place on the continent. This is the first effort yet made u 



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