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On a Hermaphrodite Specimen of Amphioxus with 

 Notes on Experiments in Rearing Amphioxus. 



By 

 J. H. Orton, D.Sc, 



Naturalist at the Plymouth Laboratory, 

 With Fignres 1-5 in the Text. 



A SPECIMEN of AmpJiioxus lanceolatus containing both sperm and eggs 

 was observed in June this year whilst experiments w^ere being conducted 

 on obtaining the larvae of this animal. The individual in which this 

 phenomenon was observed is predominantly male, and was actually seen 

 to discharge a large amount of living spermatozoa, but of the forty-three 



Ova 



Spp 



Sp.p 



Ova. 



Figs. 1 and 2. — *Views of a hermaphrodite specimen of Amphioxus from the left side and 

 the ventral region respectively. Ova are jiresent in one gonadial pouch only, 

 while all the remaining pouches contain sperm. (Drawn from the whole animal 

 stained in Delafield's htematoxylin and cleared in cedar-wood oil, X about 2J.) 

 Sp.p. Gonadial pouches full of sperm. 



large gonadial pouches present in the animal one only contains eggs and 

 the remainder sperm. On the right side of the body are twenty-two well- 

 developed gonadial pouches, two of which became nearly empty by the 

 discharging of spermatozoa ; the remainder were full of sperm when the 

 animal was preserved. On the left are nineteen pouches full of sperm 

 and one is nearly empty, but one pouch, the fifth from the anterior end, 



* I am indebted to Mrs. Orton for the drawings for Figs. 1 and 2, and for a.ssistance 

 with that for Fig. 3 ; and also to Mr. E. Ford for the lettering of the Figures. 



