vi CONTENTS 



CHAPTER III. CYCLOPIA PAGK 



Classification and structure 40 



Summary and comparison - 42 



Other records ill fishes - 43 



Causation - 44 



CHAPTER IV. MINOR ABNORMALITIES 



I. Hermaphroditism - 46 

 II. Abnormalities affecting skull or vertebral column 



(a) Shortening and curvature of the snout ; the pug-headed condition - 48 



(6) The round-headed condition 50 



(c) Defects of the lower jaw - - 51 



(d) Hump-back, twisted body, and allied conditions - 51 



(e) Local reduplication and deficiency of the notochord - 64 



III. Abnormalities affecting fins 



(a) Excess - 54 



(6) Defect 55 



(c) The so-called "tailless" condition - 56 



IV. Abnormalities of coloration 



(a) In fishes generally - - 56 



(6) In flat-fishes, associated with certain other defects 56 



V. Parasitism ... 59 



VI. Pathological conditions of the ovum or early embryo - - 60 



VII. Abnormalities having reference for the most part to single organs - 61 



INDEX TO STRUCTURES AND SUBJECTS IN TEXT AND PLATES 63 



INDEX TO SPECIES, GENERA, ETC., OF FISHES REFERRED TO IN TEXT - 70 



INDEX OF AUTHORS - . 72 



SUMMARY OF CONTENTS OF PLATES 74 

 PLATES I.-XXVI. FIGS. 1-114 



