364 Mr. A. Adams on Japanese Species ofCsecidee. 



been derived were all collected by me during my explorations 

 among the islands of the Japanese archipelago. 



Fam. CaBcidsB. 



In order to ascertain what small species of shells were found 

 in the seas of Japan, I was accustomed to reserve a portion of 

 the bottom which was brought up in the dredge, and have it 

 carefully washed and dried. In leisure moments I looked over 

 the mud and sand so prepared, and discovered many curious 

 and beautiful forms, most of them never before viewed by 

 human eye. Among them were numerous specimens of Cceca^ 

 which I have submitted to the scrutiny of my friend Dr. P. P. 

 Carpenter, who has made the knowledge of this little group 

 especially his own. His results I will now give in his own 

 words. Akasi, from which place I obtained so many, is 

 situated in the Seto-Uchi or Inland Sea. 



1. CcBcum gracile. 



" Mr. A. Adams obtained a large number of specimens at 

 Gotto and Tanabe. Unfortunately all were dead, and mostly 

 worn ; but the characters of the species are plain. The shape 

 and sculpture are almost exactly like G. elegantissimum on a 

 larger scale ; ribs generally 18-20, sharp .and distinct, with 

 wide curved interspaces. The plug is almost flat, and (the 

 specimens being weathered) the apex is not to be traced. By 

 this character and the scarcely slanting mouth it is easily 

 known from the other Japanese species. Dr. Stimpson's spe- 

 cimen had an unusual number of ribs, and this sharpness was 

 worn off. No opercula were found." 



2. Ccecum vitreum. 



" On a close microscopic comparison side by side with the 

 Teneriffe specimens, I am unable to detect any constant dif- 

 ference, either in texture, shape, size, or form of plug. A 

 large number of specimens, in fine condition, were obtained at 

 Simoda, Akasi, 0-Sima, and Tanabe. A variety has the plug 

 flatter; another variety much raised." 



3. Ccecum dextr over sum. 



'^ Several fresh specimens of this species were found at 

 Akasi and 0-Sima with the plug as variable as in the Mazatlan 

 shells." 



4. Ccecum Clarkii. 



" Several specimens of this Teneriffe form were also found 



