ADDENDA ET CORRIGENDA. 



Page 3 (57). Brancliiostotiia lanceolatuni. 



To the synonymy of species No. 1, add: 



{'' Limax lanceoJatus Pallas, Spicilegia Zoiil. x, 19, about 1770.") 



Until tbe Lancelets are more fully compared, neither our Atlantic 



nor our Pacific coast form can be distinguished from the European 



species. 



Page 5. Instead of Bdellostoma read : 

 3. PoQistotreina Gill. 



The generic name Heptatrema Dum^ril (Cuvier, Regne Anim.) has 

 2)riority over Bdellostoma Miiller. Species 3 may be named — 



3. P. StOUti (Lockington) J. & G, 



The identity of this species, thus far known only from the coast of 

 California from Santa Barbara northward, with the Chilian H. domheyi 

 is doubtful. The description, on page 57, is taken from California speci- 

 mens. The genus Polistotrema Gill (Proc. U. S. Nat. Mus. 1880, 30) is 

 distinguished by the presence of 11 to 11 gill-openings instead of G or 7, 

 the base of the tongue being between the seventh and eighth (not an- 

 terior) pair of branchiae. 



Page 7. A better generic arrangement of our Lampreys than that 

 given in the text would be as follows (omitting the character of the 

 division of the dorsal fin, which is subject to much individual varia- 

 tion): 



c. Maxillary tooth single, creacent-sbaped, with a cusp at each end. 



b. Lingual teeth pectinate 4. Entosphexus* GilL 



bb. Lingual teeth obscurely tricuspidate 5. AMMOCfETESt Dumdril. 



aa. Maxillary tooth of 2 or 3 pointed cusps close together; lingual teeth pectinate. 



C. PETROMYZONt L. 



* Species E. tridentatm (Gairdn.) Gill. 



t Including Lampetra Gray. Species A. plumbeus (Ayres) Bean: A. aweus Bean: A. 



vif/cr (Raf.) Jor. : A appendix (Dek.) J. Si, G. 



t Including Ichthyomyzon Grd. Species P. argenieus Kirt. : P. caatancus (Grd.) Bean: 



V. inarinus L. : P. d&raatua Wilder. 



807 



