ACM^EA. 45 



Numerous specimens collected by Frederick Stearns and others 

 are before me, exhibiting considerable variation. A variegated 

 specimen is figured on pi. 9, fig. 30. This species is the P. yrano- 

 striata of Schrenck. The true granostriata of Keeve (Conch. Icon., 

 f. 126) described without habitat, is very likely the same as con- 

 cinna ; but without more information it would be mischievous to use 

 that name for this or any other species. 



A. HEROLDI Dunker. PI. 2, figs. 18, 19, 20, (enlarged) ; PI. 9, 

 figs. 17, 18, 19, 20, 21. 



Shell small, ovate-elliptical, not much elevated, sculptured with 

 more or less distinct close riblets ; whitish, ornamented in various 

 patterns with brown ; vertex elevated, situated at the anterior fourth 

 of the shell's length. Inside white or bluish, brown in the middle. 

 Length 11, width 8, alt. 4 mill. (Dkr.} 



Nagasaki and Decima, Japan. 



P. heroldi DKR. Moll. Jap. p. 24, t. 3, f. 13. Acmcea heroldi 

 LISCHKE, Jap. Meeres-Conchyl. ii. p. 96. P. comilus DKR. I.e. p. 

 24, t. 3. f. 19. P. pygmcea DKR. I. c. p. 24, t. 3, f. 20. 



A small species, varying much in degree of elevation, coloration 

 and position of the apex. It passes through the same mutations as 

 most other Acmseas. I have not seen the typical form. 



Form conulus Dkr. PL 9, figs. 17, 18. 



Small, much elevated, apex more central. Length 8, breadth 6}, 

 alt. 5J mill. The figures are drawn from a specimen before me. 

 Of this form I have seen a good many examples. The radiating 

 riblets are wanting or obsolete ; most are marked with dull olive 

 or brown stripes. 



Form pygmcta Dkr. PI. 9, figs. 19, 20, 21 (enlarged). 



This is the narrow form, probably growing on fuci. It is very 

 finely striated radially. The size is smaller than the figures. 



A. DORSUOSA Gould. PI. 33, figs. 88, 89, 90 ; PL 9, figs. 15, 16. 



Shell oval, elevated conical, having the form of A. persona Esch. ; 

 solid. Apex curved forward, situated one-eighth of the shell's 

 length from the anterior end. Surface having strong irregularly 

 nodose radiating cords, separated by spaces of greater width than 

 the ribs and having occasional strongly marked concentric depres- 

 sions, indicating periods of growth arrest. Color, blackish-brown 



