CONTENTS 



Introduction 525 



The Specimens and Their Source 527 



The Drawings and Their Authorship 529 



Viviparity (Ovoviviparity) in Chlamydoselachus 531 



Breeding Season of the Frilled Shark 534 



Evidence from the Ovaries 534 



Stages of Embryos in the Uteri 535 



Duration of Gestation 538 



The Reproductive Organs of the Male Chlamydoselachus 541 



Myxopterygia — External Organs of the Male 541 



The Reproductive Organs of the Female Chlamydoselachus 542 



The Ovaries 544 



Immature Ovarian Eggs 548 



A Mature Ovarian Egg 548 



The Oviducts 549 



The Abdominal Openings . 549 



The Shell Gland • • 550 



The Uterus 552 



Right Uterus Functional 552 



Left Uterus Sometimes Functional 55/ 



Do Embryos Receive Nutriment prom Uterine Wall? 559 



The Cloacae Openings 562 



Right Cloacae Opening Predominant 562 



Female Reproductive Organs of Certain Higher Sharks and Various Rays . . 564 



Ovaries and Oviducts of Some Florida Sharks 564 



Ovaries and Oviducts of Various Rays 565 



The Encapsuled Egg of Chlamydoselachus 566 



Ellipsoidal Eggs of the Frilled Shark 567 



Normal Ellipsoidal Encapsuled Eggs 567 



Unusual Ellipsoidal Eggs with Tendriliform Processes 569 



An Elliptical Egg 569 ■ 



Some Oblong Fertile Eggs 570 



An Elongate Infertile (Wind) Egg 571 



Round Eggs of the Frilled Shark 572 



Sizes of Eggs of Chlamydoselachus Compared with Those of Other Sharks 573 



Sees of Eggs and Embryos of the Frilled Shark 573 



Sizes of Eggs and Embryos of Isurid Sharks 574 



Sizes of Eggs of the Nurse Shark 57o 



Formation of the Egg Capsules of Chlamydoselachus and of Gingly mo stoma 578 



Formation of Tendriliform Processes ..... 579 



523 



