28o 



SCIENCE. 



[Vol. XII. No. 305 



A Correction. 



In last week's Science, p. 256, first column, line 40, occurs a 

 typographical error which it may be worth while to correct. I re- 

 fer to the word ' eidography,' erroneously printed ' cidography,' — a 

 word suggested as useful in discussing surveys, and having refer- 

 ence solely to the surface form of the earth, its ups and downs, its 

 hills and hollows. The words ' hypsography ' and ' topography ' 

 are each used for this purpose ; but the first refers rather to eleva- 

 tion than to form, and ' topography ' has been and is used in differ- 

 ent senses, hence its meaning is uncertain until defined by the writer 

 using it. Marcus Baker. 



Washington, D.C., Dec. 4. 



of small fish. How have they been preserved from destruction, 

 and whence came the original stock .' Chs. B. Palmer. 



Columbus, O., Nov. 20. 



Queries. 



39. What is the Origin of Fish in Isolated Ponds } 

 — The Peninsula of Florida contains innumerable isolated ponds 

 varying from a few square rods to many square miles in area. 

 Many of these are simple hollows filled with rain-water, without 

 any connection with other waters. Some of them are on high 

 ground, where no flood can establish temporary connection with 

 other waters, through which fish might be admitted. The smaller 

 ones often dry up entirely in seasons of drought, yet when filled 

 with water they do not seem to be behind their neighbors in popu- 

 lation. They all swarm with fish, whose origin and continued 

 presence would seem to present an interesting question. For in- 

 stance : at Orange Heights, in Eastern Alachua County, which is 

 one of the most elevated regions of the State, as is plainly shown 

 by the radiating streams which rise in that vicinity, there is a small 

 pond on top of the highest elevation in all that region. I have 

 twice known this pond to be dry, yet it now contains an abundance 



40. Felspar, or Feldspar ? — Will you or some one of your 

 numerous correspondents kindly inform me which is the more cor- 

 rect designation, ' felspar ' or ' feldspar ' ? Both forms are in com- 

 mon use among mineralogists, and most dictionaries give both. 

 Phillips, in his ' Elementary Mineralogy,' 1823, gives 'felspar' in 

 the text, and in a footnote ' feldspar,' from the Germ3,n feldspath, 

 adding, " perhaps because found on the surface of some parts of the 

 country." Might it not rather be derived from the German /^A, 'a. 

 rock ' } If one knew when and how it was first used, this might 

 solve the point. J. Thorburn. 



Ottawa, Can., Nov. 29. 



41. The "Supernumerary Molar" in Man.— Not many 

 days ago there was a very excellent young dentist at work at Fort 

 Wingate, N. Mex., and while there a white man of some thirty-five 

 years of age presented himself to have extracted what he termed 

 " an extra tooth " in his upper jaw. Happening in, I saw this rare 

 anatomical structure immediately after its removal. It was a small, 

 transversely ellipsoidal tooth, with a single, conical, peg-like fang,, 

 the tooth itself having developed at its buccal aspect a small addi- 

 tional cusp. This tooth was situated directly posterior to the upper 

 wisdom tooth or last molar of the left side, and in contact with it. 

 I am aware that this rare supernumerary molar in man is alluded 

 to in the more extensive works upon dentistry, but I would be glad 

 if some reader of this notice will inform me where I may find the 

 best biological account of this structure in man, as well as its sig- 

 nificance, and whether it has ever been observed in any of the 

 Simiina. R. W. Shufeldt. 



Fort Wingate, N. Mex., Dec. i. 



IN THE SELECTION OF 



A CHOICE CIFT 



For Pastor, Parent, Teacher, Child, or 

 Friend,both elegance and usefulness will be found 

 combined in a copy of Webster's Unabridged. 



JHEBSTE^^ I" "l 

 lOIGTWNAfi^jllfBIMami 



Besides many other valuable features, it contains 



A Dictionary 



of 118,000 Words, 3000 Engravings, 



A Gazetteer of the World 



locating and describing 25,000 Places, 



A Biographical Dictionary 



of nearly 10,000 Noted Persons, 



A Dictionary of Fiction 



found only m Webster, 



All in One Boole. 



3000 more Words and nearlv 2000 more Illus- 

 trations than any other American Dictionary. 

 Sold by all Bo'oksellers. Pamphlet free. 

 G. & C. MERRIAM & CO., Pub'rs, Springfield, Mass. 



HYPNOTISM 



OR 



MESMERISM 



BY 



CHARLES B. CORY. 



Cloth Edition, 50 Cents. 



By lUA Waugh, author of 

 "vVee Babies." 48 large 



quarto pages. In colors. S9-00. 



•'Here are pictures aud stories, whatever your mood, 

 To help you all amile, and make yon all good." 



WORTHINGTON'S ANNUAL SlgiS' en^r^ing"^ 



and colored plates. 4io, boards. $1.50. 



WORTHINGTON CO., 747 B'way, N. Y. 



SCIENTIFIC BOOKS. 



Catalogue of Books relating to Civil, Mechanical, 

 Electncal, and Mine Engineering, and Manufacturing 

 Industries sent free to any address. 



E. & F. N. SPON, 



12 Cortlandt Street, New York. 



W.H.WALISLEY&CO. 



SUCCESSORS TO 



R. & J. BECK, 



1016 Chestnut Street Phila 



Microscopes and all 

 Accessories and Ap- 

 paratus. Photograph- 

 ic and Photo-Micro- 

 graphic Apparatus and 

 Outfits. 



Spectacles, Eye 

 Glasses, Opera and 

 Marine Glasses, etc. 



Illustrated Price List 

 mailed free to any ad- 

 dress. Mention Science 

 in corresponding with us. 



J. GRUNOW 



631 Sixth Avenue, N 



Established 



Microscope Stands, 

 Oil Immersion Object- 

 ives and Abbe Con- 

 densers for Bacterial 

 and Histological work, 

 of Objectives, Camera 

 Lucida and other ac- 

 cessory apparatus. 



GET 



THE NEW 



ACiVIE W 5 

 WIICROSCOPE 



$28.00. 



Send for complete catalogue 

 It, and sample of The Micro- 

 scopical Bulletin. 



JAMES W. QUEEN & 00. 





Schools. 



EW Haven, 



TWrRS. CADY'S SCHOOL FOR YOUNG LADIES. 

 ■'•'•*• Prepares for Smith and Wellesley, and admits to- 

 Vassar by Certificate. Circulars. Early application- 

 necessary. 



New York, Ta 

 AT MOUNT HOPE LADIES SEMINARY, 

 $300 pays board and tuitions per school year, 

 and art only extras. Beit advantages with homi 

 Opens Sept. 26th. 



ROBT. C. FLACK. A.M., Princip 



OCHOOL OF GEOLOGY, UNIVERSITY OF 

 ^^ Texas. Conveniently situateti in a remarkably di- 

 versified field for original investigation. Offers special 

 facilities to specialists and post-graduate students. Edu- 

 cational series collected and exchanged. For circulars- 

 address Proctor of University. Austin, Tex. 



Vermont, : 



VERMONT EPISCOPAL INSTITUTE. Boarding 

 School for Boys. Prepares for College or Business. 

 Military drill. Terms moderate. Fifty-seventh half- 

 year opens September 3, i888. Send for catalgue. 



H.H. ROSS, A.M., Principal. 



