INDEX TO STRUCTURES AND SUBJECTS 



69 



Tubercles, spines, and rough scales present on underside of 



ambicoloured flatfish, 58, 

 Twinning, xi, 5, 7, 30, 37. 



Twisting of body or tail. See under hump-back. 

 Types of double monstrosity, 1, 3, G, 8, 28 : of anomalous 



development in eggs of pike, 10. 



Unioval, duplicity, xi, 7, S : triplicity, 33-S9. 



Urinary bladder or opening, 12 (normal) : 21 (Cl. v.) : 32-23 



(Cl. VI.): S3 (anakatadidymus) : 34, 48 (hermaphroditic 



trout) : Bl and BV in XIX. 77-81 : XXII. 94, 96 (triple 



monster). 

 Utricle, 17 (Cl. n.): 34 (triple monster): IV. 17 (s. trans. 



norm.): V. 21 (s. horiz. norm.): XIV. 50 (s. trans. Cl. 



ii.): UtrinXX. 82 (Cl. n.). 



Valve, spiral, variation, 62. 



Vein. See under cardinal, caudal, jugular, yolk-sac. 



Vent, SO-23 (Cls. v.-vi.): S3 (anakatadidymus): Sit (triple 



monster): XIX. 81 (01. vi.b): XXII. 94-95 (triple 



monster). 

 Ventral edge membrane (incl. anal fin), IS (normal) : 20 (Cl. v.) : 



81-$% (Cl. vi.) : 23 (anakatadidymus) : 34 (triple monster) : 



54 (doubling in goldfish) : 55 (absence or malformation) : 



VI. 26 (s. trans, norm.): VI. 29, VII. 30, 31 (s. trans. 



Cl. VI.) : VII. 32-34 (triple monster). 

 Ventral union, S, 7, S3, S3. 

 Ventricle III., 41-42 (cyclopia) : III. 14-15 (s. trans, norm.) : 



V. 21-22 (s. horiz. norm.) : X. 39-40, XII. 43-44 (s. horiz. 



Cl. i.) : C3rd Fin XVIII. 69-71 (normal, Cl. I., Cl. n.) 



XXI. 91-93 (diagrams) : XXIV. 106 (parasitism) : XXV. 



107-108 (cyclopia). 

 Ventricle IV. See also medulla. IV. 17-18 (s. trans, norm.) : 



V. 21 (s. horiz. norm.): X. 39, XII. 43-44 (s. horiz. 



Cl. I.) : XV. 52-53 (s. horiz. Cl. in.) : C4th V in XVIII. 



69-71 : XXI. 90, 93 (diagrams) : XXVI. Ill (semi- 



cyclopia). 

 Ventricle of heart, 19-SO (Cls. in.-iv.): IV. 18 (B. trans. 



norm.): XVI. 54 (s. horiz. Cl. ill.): V in XIX. 73 



(normal), 74 (Cl. in.), 75 (Cl. n.). 

 Vertebral column, in twisted body, etc., 51-53. See also 



notochord, etc. 



Vertebrate, 5 (ova) : 8, 28, 31, 38 (double and multiple mon- 

 strosity). 



Visceral arch I. (incl. Meckel's cartilage), 11 (normal) : 13 

 (Cl. I.): 15 (Cl. II.): 41-43 (cyclopia): III. 13-16 (s. 

 trans, norm.): VIII.-IX. 35-37 (s. trans. 01. I.): XIII. 

 47-48, XIV. 49-50 (s. trans. Cl. n.): XVI. 54 (s. horiz. 

 Cl. HI.) : g and g' in XVII. 56 (normal), 58 (Cl. I.), 60 

 (Cl. II.) : Meek in XVIII. 64 (Cl. I.), 65 (Cl. n.) : XXI. 

 88, 91 (diagrams). See also under jaw. 



Visceral arch II., hyoid, 11 (normal) : 13 (Cl. I.) : 15 (Cl. n.): 

 41-42 (cyclopia) : 51 (defective lower jaw) : III. 15-16 

 (a. trans, norm.): VIII.-IX. 36-37 (s. trans. Cl. I.): 

 XIV. 49-51 (s. trans. 01. U.) : h in XVII. 56 (normal), 

 58 (01. i.), 60 (01. n.). See also XVIII. 64-65: XXI. 

 88, 91 (diagrams). 



Visceral arch III., 11 (normal) : 13 (01. i.) : 17 (01. n.) : III. 

 16, IV. 17-18 (s. trans, norm.) : VIII.-IX. 36-37 (s. trans. 

 Cl. I.): XIV. 51 (s. trans. Cl. n). See also XVIII. 64 

 (01. i.), 65 (Cl. ii.). 



Visceral arch IV., IV. 17-18 (s. trans, norm.): XIV. 51 (s. 

 trans. 01. II.). 



Visceral arch V., as under above. 



Visceral arch VI., IV. 18 (s. trans, norm.). 



Vomer, in pug-head, 49. 



Weight of centra in twisted body, 53. 



Wolffian body, IS (normal): VI. 25 (s. trans, norm.): XVI. 



54, 55 (s. horiz. Cl. m.): HK in XX. 83 (normal), 84 



(01. i.), 86 (Cl. IV.) : XXIII. 99 (triple monster) : XXVI. 



1 13 (s. trans, absent notochord). 

 Wolffiau ducts, IS (normal) : 14 (01. I.) : 18 (Cl. n.) : 19-S3 



(Cls. m. -vi.): SB (hemididyinns) : 34 (triple monster): 



IV. 19, VI. 24-25 (s. trans, norm.) : VI. 27-29 (s. trans. 



Cl. VI.): WD or CWD in XIX. 76-81, XX. 83-87: 



XXII. 96, XXIII. 98 (triple monster). 



Yolk, IV. 19, 20, VI. 24 (s. trans, norm.) : VI. 27 (s. trans. 

 Cl. vi.): IX. 38 (s. trans. Cl. i.) : XVI. 54 (s. trans. 

 01. in.): XXIII. 97-99 (triple monster): XXVI. 114 (s. 

 trans. 01. v.). 



Yolk -sac, S (exhaustion of yolk) : S-4 (union by yolk-sac) : 

 6-7 (overgrowth of blastoderm) : S (more than one blasto- 

 derm) : S3-S4 (in anakatadidymus) : 25 (in hemididymus) : 

 SO (yolk and osmosis) : 61 (double-yolked eggs). 



Zig-zag fission, 27 (supposed in katadidymus). 



