ASTKALU'M. '_>27 



the folds generally eighteen to twenty in number on the last whorl, 

 pub-interrupted <>r excavated about the middle, produced at the 

 sharply earinate periphery into squamose square somewhat descend- 

 ing spines; base flattened, radiately striate, and with tour to six 

 concentric irregular subnodose line; aperture very oblique, wide: 

 lip scalloped, chanelled at outer angle; coluniella bidentate below, 

 its face slightly grooved. Alt, 40, diam. 45 mill. 



Honduras (Reeve); West 

 T. corolla Reeve is synonymous. 



A. TrMKiiosrM Phil. PI. 64, figs. 57, 58. 



This thick-shelled Trochid stands near to T. ccelatus, but is distin- 

 guished by the following characters; the whorls are flat, not arched, 

 in the middle; the superior nodules are situated near to the suture, 

 are hemi-sphserical and solid ; the last whorl has but a single row of 

 nodules ; the carina is sharper, the base flatter, with only three con- 

 centric nodose line ; the aperture is lower, more rhomboidal ; color 

 reddish brown, more or less verging on violet. 



Coast of Mexico. 



I have translated from Philippi the more important portion of his 

 description. I am unable to identify the form with any shells I have 

 seen. It is probably immature. 



A. r.LTCATt'Li-M Philippi. PI. 64, figs. 62, 63. 



Shell strictly conic, imperforate, yellowish white ; whorls planu- 

 late, the last acutely angled, obliquely plicate, the folds small, about 

 forty in number on the body-whorl, interrupted by two spiral fur- 

 rows, of which the upper is in middle of the whorl, the lower midway 

 between that and the wavy lower margin of the whorl ; base nearly 

 flat, with six strong, elevated concentric lira?, and radiating lamel- 

 lose striae. Alt. 23, diam. 25 mill. 



Habitat unknown. 



Known to me only by Philippi's figure and description from which 

 the above is taken. It probably does not belong to this group. 



Subgenus IMPERATOR, Montfort, 1810. 



Shell large, trochiform, concave and umbilicate below, carinated 

 and spinose at periphery, whorls convex and grauulose above ; opej-- 

 culum oval, outside smooth, obsoletely unicostate. 



Amtralo-Zealandic Pro r/nrc. 



Canthorbis Swainson, 1840, and in part Guildfordia Gray, 1850, 

 are synonyms. 



