The variations and ecological distribution of the snails of the genus Io . EXPLANATION TO PLATE 4. (Showing the development of the shell and its spinosity.) HOLSTON RIVER SYSTEM—continued. Figs. 1-13. Lot 94. Group 13. Bluff City, Tenn. Enlarged 1/6. Figs. 14-20. Lot 88. Group 16. Rogersville, Tenn. Enlarged 2/5. Figs. 21-34. Lots 87 and SS. Group 16. Rogersville, Tenn. Natural size. Figs. 35-47. Lot 90. Group 17. Cobb Ford, Tenn. Natural size.100

The variations and ecological distribution of the snails of the genus Io . EXPLANATION TO PLATE 4. (Showing the development of the shell and its spinosity.) HOLSTON RIVER SYSTEM—continued. Figs. 1-13. Lot 94. Group 13. Bluff City, Tenn. Enlarged 1/6. Figs. 14-20. Lot 88. Group 16. Rogersville, Tenn. Enlarged 2/5. Figs. 21-34. Lots 87 and SS. Group 16. Rogersville, Tenn. Natural size. Figs. 35-47. Lot 90. Group 17. Cobb Ford, Tenn. Natural size.100 Stock Photo

RMID:2ANB8Y4

Image details

Contributor:

The Reading Room / Alamy Stock Photo

Image ID:

2ANB8Y4

File size:

7.1 MB (364.9 KB Compressed download)

Releases:

Model - no | Property - noDo I need a release?

Dimensions:

2041 x 1224 px | 34.6 x 20.7 cm | 13.6 x 8.2 inches | 150dpi

More information:

This image is a public domain image, which means either that copyright has expired in the image or the copyright holder has waived their copyright. Alamy charges you a fee for access to the high resolution copy of the image.

This image could have imperfections as it’s either historical or reportage.

Search stock photos by tags

bookcentury1900 bookdecade1910

Similar stock images

RM2ANAPRJ–The variations and ecological distribution of the snails of the genus Io .

RM2ANAR85–The variations and ecological distribution of the snails of the genus Io .

RM2ANBAX4–The variations and ecological distribution of the snails of the genus Io . a>^; -..c..^^ ^ / 7 HATTANOOGA £/^.

RM2ANANY2–The variations and ecological distribution of the snails of the genus Io . EXPLANATION TO PLATES ()-9. (Width <if sh *^ 1 V , ^ f Xy

RM2ANAMHK–The variations and ecological distribution of the snails of the genus Io . 1 I EXPLANATION TO PLATES 10-13. (Shell Index.) Plattings of quantitative data to show the average degree of globosity of the aperture ofthe shell in terms of the diameter of the shell, the shell index, by groups, throughout the Ten-nessee system.106.

RM2ANBAE7–The variations and ecological distribution of the snails of the genus Io . 17829°—1.5- EXPLANATION TO PLATE 2. Relief map of the soutlicni Apjialachian Region, showing the topography and drainage ofthe Tennessee River system above Chattanooga. From the United States Geological Survey.96 1 • ?J i ? 1 , ?? 1 81° 8C li

RM2ANAJGJ–The variations and ecological distribution of the snails of the genus Io . 65 «s .67 .eg-tE!«0LGLQaosiTy h PekCtNT 75 .75 .77 .79 .6i .9! .«5 ?«. EXPLANATION TO PLATES 14-17. (Height of S])ines.) Plattings of quantitative data to show the average height of spines, by groups, throughoutthe Tennessee River system.108

RM2ANBBDJ–The variations and ecological distribution of the snails of the genus Io . resencein the smooth shells may be looked upon as so much contamination from another strain withwhich they are fertile when crossed. Undulations progressively decline with departure fromthe South Fork of the Holston. The relations of these forms seem relatively simple. On theother hand, spinosity presents a much more complex problem, because it not only varies indegree, but also in the time of its appearance in the life of the animal. It may develop only latein life, or it may do so from its earHest postembryonic develo

RM2ANAHP9–The variations and ecological distribution of the snails of the genus Io . EXPLANATION TO PLATES 14-17. (Height of S])ines.) Plattings of quantitative data to show the average height of spines, by groups, throughoutthe Tennessee River system.108. Plate 14 Height of Spines POWELL RIVER Groups 1—5 Group 2. 1.. ?, ?, Group 3. -..-.....„„ Group A Group <5.««. .«. .^ .«. .*M 101 91 818877665544332 as o.a I Height of Spines 3.3 5.8 4.3 lOOOi 950

RM2ANBBMG–The variations and ecological distribution of the snails of the genus Io . CO ^Oa,, MEMOIRS i»^,1.wlf Sectional Lsbtcay OF THE NATIONAL ACADEMY OF SCIENCES .^e^T^^rO^^ V^^^^ -^r^S^l Voliame XII gecv-cv-^- P»art II SECOND ]yj tUM:OIR WASHINGTON1915. ISTATIOlSrAL ACADEMY OF SCIEISTCES. Volume XII. SECOND MEMOIR. THE VARIATIONS AND ECOLOGICAL DISTRIBUTION OF THE SNAILS OF THE GENUS 10. BY CHAS. C. ADAMS, NEW YORK STATE COLLEGE OF FORESTHY,SYRACUSE, NEW YORK. CONTENTS Page. I. Introduction 7 II. Habits and life history of lo 8 III. The races and forms of ib 10 IV. The geographic relations of the s

RM2ANATYT–The variations and ecological distribution of the snails of the genus Io . EXPLANATION TO PLATE 4. (Showing the development of the shell and its spinosity.) HOLSTON RIVER SYSTEM—continued. Figs. 1-13. Lot 94. Group 13. Bluff City, Tenn. Enlarged 1/6. Figs. 14-20. Lot 88. Group 16. Rogersville, Tenn. Enlarged 2/5. Figs. 21-34. Lots 87 and SS. Group 16. Rogersville, Tenn. Natural size. Figs. 35-47. Lot 90. Group 17. Cobb Ford, Tenn. Natural size.100. EXPLANATION TO PLATE 5. (Showing the development of the .^hell and its t^pinosity.)HOLSTON RIVER SYSTEM ContilUied. Figs. 1-5. Lot 90. Group 17. Co

RM2ANA9JN–The variations and ecological distribution of the snails of the genus Io . Plate 25 Spine Index Height of Spines. Distance Between Spines NOLICHUCKY. FRENCH BROAD,TENNESSEE RIVERS 1 Groups 19-27 kouchucxy Group f9 ^4..t..t..t.H Group 20 .„,...mmm FK£NCH enoADGroup 21 —?—?»??- Group M Group 23 ^^%»s%%M»Group !! Group 25 .^ — . Group !6 Group a? .47 .52 EXPLANATION TO PLATE 26. (Dimensions of the sliell.) Table showing the diameter of shell, and shell index, by gi-oups, throughout the TennesseeRiver system. 114 Memoirs National Aca demy 3f Sciences, XII. Second Memoir, PI. 25. Number ofshells