8. CycLosTOMA coxcENTRTCUM. This mny be a variety of C. varia- 

 bile ; it is chiefly distinguished by having the lamellae between the 

 inner and outer peritremes so much produced as to appear like numer- 

 ous concentric margins ; by having the lip reflected farther back ; by 

 a more slender general form, the mean divergence being 33" to 35°. 

 The lip is reddish purple, with darker rays of the same conspicuous 

 in the more simple lip of the young, and the square sutural spots are 

 always faint. 



9. Cyclostoma serriferum. Shell ovate-conic, moderately elon- 

 gate ; reddish brown, with a series of rather dark spots of the same ; 

 with very thin and sharp tranverse perpendicular rather distant lamella:;, 

 which are serrated by a few faintly impressed spiral lines : spire with 

 convex outlines ; apex truncate with the loss of about three whorls ; 

 remaining whorls four and one half, moderately convex, with a well 

 impressed suture ; last whorl scarcely detached from the penult whorl 

 near the aperture, which is orbicular ; inner peritreme not produced (?) ; 

 outer peritreme shining, well expanded, except opposite to the penult 

 whorl ; umbilicus narrow, but extending through the truncate apex. 



Mean divergence about 40''; length 57 inch ; greatest breadth .35 

 inch ; least breadth .275 inch. 



This may possibly be an accidental variety of C. Grayanum or of 

 some other of this group. The only specimen which I have does not 

 appear to have the lip fully developed with age. 



10. Cyclostoma decussatulum. Shell moderately elongate, 

 ovate conic ; whitish, with brown spiral bands, which are more dis- 

 tinct on the lower whorls ; elegantly and finely decussated with nu- 

 merous close-set transverse strong ^rounded raised lines ; spire with 

 convex outlines : apex truncate with the loss of two or two and one 

 half whorls; four and one half to five whorls remaining, convex, with 

 a deep suture ; aperture nearly circular ; inner peritreme moderately 

 produced and reflected ; outer peritreme moderately expanded, concen- 

 trically striated ; umbilicus narrow, but extending through the trun- 

 cate apex. 



Mean divergence about 50°; length .58 inch; greatest breadth .42 

 inch ; least breadth .32 inch. 



This species does not answer to the description and figures of C 

 mirabilc, Gray, to which it must be nearly allied. 



11. Cyclostoma mirandum. Shell elongate, conic ; brownish 

 white, with a series just below the suture of large distant square brown 

 spots, and with on the upper whorls three, and on the last five narrow 

 somewhat interrupted brown spiral lines ; covered with closely-set 

 rounded transverse raised lines; which are decussately crenulated by 



