THE NAUTILUS. 105 



oaks, sometimes to a height of seven feet and seem to be given 

 greatly to breeding. 



" I have introduced a number of other snails from Cuba and 

 Bimini including some of the land operculates, but have never 

 found living or dead specimens since. That does not prove 

 that they may not be living, as it seems to take a long time for 

 a species to become established. Until a short time ago I sup- 

 posed that no Cuban Liguus were living in my hammock. I 

 have none of the original stock of these that I can be sure of; I 

 simply introduced the things for ' company ' and not for any 

 ' scientific results.' " 



I think the above is well worth putting on record. GEO. H. 

 CLAPP. 



SOME RARE SHELLS COLLECTED IN PUGET SOUND, WASHINGTON, 

 DURING JULY, 1918. Thinking it would be of interest to the 

 readers of the NAUTILUS, I send you a short list of some of the 

 very rare species we collected this summer at the Biological 

 Station of the University of Washington at Friday Harbor, San 

 Juan Island. 



Thyasira bisecta Conrad. 



This rare shell we dredged in mud in between 3 and 4 fms. 

 Three live specimens and a few dead ones were obtained. 



Macoma nasida kelseyi Da.ll. 



This species we found with the above; the specimens were 

 larger than those from California. 



Thracia curia Conrad. 



One specimen of this species was obtained in 25 fms. between 

 San Juan Is. and O'Neal Island. 



Thracia trapezoides Conrad. 



This species is the pride of the collection. So far as we have 

 been able to find out, this has never been reported living. One 

 living and two dead specimens were obtained in about 20 fms. 

 off O'Neal Island. This with the first two are found in the 

 Pliocene at San Pedro, Cal. 



