THE BREEDING HABITS, REPRODUCTIVE ORGANS, AND 

 EXTERNAL EMBRYONIC DEVELOPMENT OF CHLAMTDOSELACHUS, 

 BASED ON NOTES AND DRAWINGS LEFT 

 BY BASHFORD DEAN 



By E. W. GUDGER 



Honorary Associate in Ichthyology 

 The American Museum of Natural History 



INTRODUCTION 



While on a leave of absence from Columbia University, Prof. Bashford Dean spent 

 parts of 1900 and 1901 in Japan. There he collected and studied many rare and little- 

 known marine animals — particularly certam archaic fishes and their eggs and embryos. 

 That these collections were extensive, we know since there is a letter by him stating that 

 when shipped to America by freight they filled seven cases. In this shipment were 

 several adult frilled sharks, and others were sent to him later. Of the disposition of these 

 and of Dean's generosity in sending specimens of this fish to various European investi- 

 gators, Gudger and Smith have written (1933, pp. 250-252). 



Dean's embryological materials were collected to enable him to follow and to il- 

 lustrate the early life histories of two primitive elasmobranchs — the frilled shark, Chlamy- 

 doselachus anguineus, and the Port Jackson shark, Heterodontus (Cestracion) phiUppi. 

 Back in America, Dean found gaps in his materials and figures, so he returned to Japan and 

 did further work on these fishes during the months from May to October, 1906. Further- 

 more, other frilled-shark material was still later collected in Japan and sent to him in 

 America. I have records of specimens received by Dean on February 10, 1911, and on 

 January 13, 1912. I have been unable to trace these specimens, but other lots came to him 

 and were deposited in the Dean collection in the 2;ooIogical museum of Columbia Univer- 

 sity. Among the specimens loaned from Columbia are four lots of young embryos without 

 yolk sacs labelled "Bought in Tokyo Market, February 4, 1913; April 4, 1913; January 22, 

 1914; April 23, 1917"- His Japanese collectors evidently found the fresh-caught adult 

 sharks in the Tokyo market, opened the fish, cut the embryos from the uterine eggs, 

 and sent these embryos to Dean. 



Since the above was written, I have learned that in 1917 Dr. Dean paid a flying visit 

 to Japan to collect armor and objects of art for the Metropolitan Museum of Art, in 

 which he was at that time curator of arms and armor. He reached Japan on March 28 and 

 embarked for the U. S. on May 19. This I have from a member of the party and from 

 his letters to Mrs. Dean. Hence he was in Japan when five embryos (to be referred to 

 later) were collected on April 23. These and the ones referred to above, were obtained 

 by his friends (whom he names in these letters), and preserved for him. The specimens 

 collected in 1917 (and possibly the others listed with them) were brought back by him in 

 May- June of that year. 



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