

vi CONTENTS 



Chapter III. Cyclopia paok 



Classification and structure ...-....-.40 



Summary and comparison - - - - 42 



Other records in 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 



(b) The round-headed condition .--.----50 



(c) Defects of the lower jaw --------- 51 



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



(e) Local reduplication and deficiency of the notochord - - - 54 



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 



(b) 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 



