H 



The present paper is not designed as a taxonomic treatist, 

 and the writer has no desire to formally synonymyze the forms 

 of Thais of the lapillus type found upon our west coast with 

 the Atlantic species, although he believes that would be a log- 

 ical procedure. 



In a paper published in 1910 Dr. E. G. \anatta placed a 

 considerable number of trivial names that had been appli ed 

 to our west coast forms as synonyms under three species which 

 he regarded as valid:- 



Tbais plicata Martyn, 1789, with a list of six synonyms, 

 including Buccinum lamdlosum GmtVm^ ^79^- 



Thais lima Martyn, 1784, with five synonyms, including 

 Purpura canaliculata Duclos, 1832, and Purpura decemcostata 

 Middendorf, 1849. 



Thais emarginata Deshayes, 1839, with several synonyms. 



In the year 1915 Dr. W. H. Dall published a very detailed 

 monographic revision of our west coast Thaisidae^ in which he 

 expressed his views regarding the proper classification of this 

 group. In dealing with these highly polymorphic forms, which 

 present intergrading series of a most far reaching nature, he 

 followed the traditional method of dealing with such prob- 

 lems and initiated a series of highly artificial divisions, leaving 

 it to the individual to fit his specimens into the system as 

 best he might. The difficulty of harmonizing this traditional 

 treatment with the modern trend in taxonomic procedure is 

 quite apparent. 



In his treatment of the group representing Thais lamellosa 

 Dall gives an exhaustive summary of the bibliographic refer- 

 ences to this species, tracing the permutations in the names 

 that have been applied to this variable form by various au- 

 thors through six changes in the designation of the genus and 

 ten trivial names that have been applied since it was first 

 called to the attention of students of the Mollusca. 



In this paper Dall points out that the name of this species 

 Utilized by Vanatta is invalidated under the laws of priority, 

 which leaves Thais lamellosa Gmelin as the accepted name. 



