284 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



formula, 49, 18, 12. The species was found off Peru, 

 and has not been re-discovered, and the type specimens 

 have been lost. The true position and characters cannot, 

 therefore, be determined till new specimens are described. 

 Dr. 1). S. Jordan suggests that this species is identical 

 with B. call fornien.se, and indeed the two species are 

 difficult to separate, for Dr. Eigenmaim, who found a 

 shoal of lancelets in San Diego Bay, California, in 1891, 

 suggested that they were B. elongatum, while Kirkaldy 

 states they were probably B. calif orniense. It is not 

 improbable that the two species are identical, for the 

 extension of B. elongatum along the coast from Peru to 

 California is not unlikely. It is stated that oral cirri 

 are absent in B. elongatum. This is unlikely, and their 

 apparent absence is probably due to the shrinking and 

 bad 2 3reserva ti 011 of the material. Moreover, their 

 myotome formulae do not diifer markedly, and in view 

 of the great variation of this character, it is probable that 

 they are only extreme variations of the one species. B. 

 elongatum has a formula of 49, 18, 12, while B. 

 calif orniense has 45, IT, 9. 



B. capense, a new species formed by Gilchrist for a 

 South African form, is still more closely related to the 

 Californian one. The only differences between them are 

 (1) the presence of an eye spot in B. calif orniense and its 

 absence in B. cajjense, and (2) the myotome formula. 

 Gilchrist admits that his specimens were much damaged, 

 and this may account for the absence of the eye spot, for 

 it is very improbable that that structure is really absent. 

 The damaged state of the specimens also prevented him 

 from studying the variations in the myotome formula, 

 and it is probable that, had lie done so, he would have 

 found that the myotome foi inula of B. cape use overlapped 

 thai of B. calif orniense. The difference noted between B. 



