'298 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



Indian species in the Louisiade Archipelago and sub- 

 sequently in Sandal Bay, Lifu, although it is a fact that 

 there is a strong Caribbean element in the fauna of the 

 Indo-Pacific." This last remark has received further 

 support in the finding of A. lucayanum (the identical 

 species of Andrews, and known only previously from the 

 Bahamas) in the seas round the Maldives, and this is one 

 more link in the chain of evidence in support of the 

 current theory that there was in former times a continuous 

 connection between the Pacific and Atlantic Oceans. 



Finally, species of Cephalochorda are found in the 

 littoral waters of all the great continents, and we may 

 feel sure that the more fully these littoral waters are 

 worked, especially of the seas round Africa, about which 

 we at present know so little 1 , the more widely and 

 generally distributed will we find Amphioxus to be. 



I must express my thanks to Professor Herdman for his 

 great kindness and help in the preparation of this paper, 

 and also* for valuable aid in dealing with the literature 

 of the subject. 



I append a table for the identification of the species 

 of the Group. 



CEPHALOCHORDA, Lankester, 1877. 



Family Branchiostomid.e, divided into two Genera: — 



Genera : — 



Genus I. Branchiostoma — Metapleural folds end 



symmetrically just behind the anus, 



separated by the ventral fin ; gonads 



disposed in two lateral series, ventral fin 



a In support of this assertion I notice that in Mr. F. Cooper's 

 paper on the Cephalochorda of the Maldives (which has appeared 

 while the present paper was going through the press) it is stated that 

 Mr. Crossland has found two species, A. maldivense and A. lucayanum, 

 off Zanzibar, a region hitherto unworked. 



