CONTENTS OF No. 180.-New Series. 



MEMOIRS : 



PAGE 



On the Structure of the Excretory Organs of Amphioxus. Part I. By 

 Edwin S. Goodrich, M.A., Fellow of Merton Colleee, Oxford. 

 (With Plate''27) 493 



A Contribution to the Morphology of the Teleostean Head Skeleton, 

 based upon a Study of the Developing Skull of the Three-spined 

 Stickleback (Gasterosteus aculeatus). By H. H, Swinnerton, 

 B.Sc, from the Zoological Laboratory, Royal College of Science, 

 London. (With Plates'^S— 31 and 5 Text Illustrations) . . 503 



The Development of Admetus pumilio,Koch: a Contribution to 

 the Embryology of the Pedipalps. By L, H. Gough. (With 

 Plates 32 and 33) 595 



On the Teeth of Petroinyzon and Myxine. By Ernest Warren, 

 D.Sc, Assistant Professor of Zoology, University College, London 

 (With Plat^34) ',631 



Typhlorhynchus nanus: a New Rhabdocoele. By F. E. Laidlaw, 

 B.A. (With Plate 35) .637 



