96 THE NAUTILUS. 



NOTE ON ACTEOCINA. 



BY WM. H. BALL. 



Mr. A. M. Strong in the October NAUTILUS calls attention to 

 some apparent discrepancies in the distribution of the West 

 Coast species of this genus as recorded in my " Summary " of 

 the West American Shells. 



My record of the distribution as published is taken from the 

 series contained in the collection of the National Museum and 

 not (except when otherwise verified) from the literature. The 

 only real discrepancies in Mr. Strong's table are those of A. 

 culcitella ( -f- cerealis) and A. infrequens C. B. Adams. I have 

 127 different lots of A. culcitella comprising about 500 specimens 

 and see no reason for changing my identification. Mr. Strong 

 errs in supposing that the Kodiak fauna is Arctic. On the con- 

 trary it is Oregonian and contains a large proportion of Puget 

 Sound species. The question of the identity of cerealis and 

 culcitella has been in dispute for more than forty years. The 

 trouble is that eliminating cerealis one finds no specimens of 

 young culcitella, and they are generally found together. I pre- 

 sume it will take anatomical study to settle the question. The 

 color of the periostracum varies from white to ruddy brown just 

 as in Cylichna alba. 



In the case of infrequens, in taking off the distribution from 

 the collection, I did not notice that the Santa Monica specimens 

 were fossil. Our "live" series begins at Cape St. Lucas with 

 the Panamic fauna. Otherwise there is nothing to change in 

 my record of distribution. 



I may add that the fine spiral striation is inconstant in 

 strength in these shells, as is also the carination at the shoulder. 

 A good example of this variability will be found in any large 

 series of our common East Coast Acteocina canaliculata Say, 

 where the channel at the shoulder varies from clear-cut and 

 sharp, to a state so obsolete as to be hardly perceptible. 



Mr. Strong's criticisms are welcome, and I hope he will con- 

 tinue his scrutiny of what appear to be doubtful cases. It is 

 only by such means that we shall finally attain a perfect list of 

 the fauna. 



