Although the correct systematic name of the commonest species is Branchiostoma lanceolatum (Pallas), it is convenient in non-systematic usage to employ the term "Amphioxus," which is in general use in zoological laboratories.
Quart. Journ. Micr. Sci. xlv. March 1902, p. 493.
The cerebral eye and the pigment spots of the spinal cord are especially prominent in the oceanic species Branchiostoma pelagicum, Günther.
The mesoblastic somites in Figs. 84 and 85 are all derivatives of the larger posterior pair of coelomic pouches, the smaller more anterior ones not being shown. For further details in regard to the coelomic pouches see MacBride, Quart. Journ. Micr. Sci. xliii. p. 351, 1900.
I have to thank Mr. Walter Tattersall, B.Sc., working in my laboratory, for a detailed summary and discussion of the various published schemes from which this table has been drawn up. He has also filled up for me the map (Fig. 90) showing the geographical distribution of the species. (See also Trans. Biol. Soc. Liverpool, vol. xvii. 1903, p. 269.)