BATHYBEMBIX AEOLA. 101 



argenteo-nitens Lischke and perhaps also with T. Alwinae 

 Lisehke. Watsou (1. c.) has also stated its affinity to argenteo- 

 nitens. According to this last author a second specimen 

 has been observed by Dr. Hoek, which was larger, with 

 the basal threads more numerous and a covered umbilicus, 

 leaving a mere chink. 



Afterwards Pilsbry has described (The Nautilus, Vol. VI, 

 1893, p. 105) a new species named Calliostoma Crumpii, 

 referred on page 133 to the genus Bathybembix and figured 

 on Plate II, fig. 3, of the same volume, and E. A. Smith 

 described Bathybembix Wood-Masoni (Ann. and Mag. Nat. 

 Hist. Vol. XVI, 1895, p. 7, fig.). 



AmoDgst the Trochidae of the collection of the Leyden 

 Museum, I found a shell collected by von Siebold in Japan, 

 clearly belonging to the genus Bathybembix, but apparently 

 not agreeing with any of the described species; however 

 the sculpture of B. aeola proved to be identical with that 

 of the upper whorls of the shell under consideration, so that 

 I am convinced that this latter is the adult state of B. 

 aeola. As the character of the adult shell is rather dif- 

 ferent from the young one, I thought it useful to describe 

 and figure it. Unfortunately the embryonic whorls are 

 wanting in my specimen, but 2 whorls with the 3 spirals, 

 crossed by longitudinal lirae are present; of these lirae the 

 median one first disappears and afterwards the inferior, 

 while the infra-sutural one persists till near the aperture; 

 the puckerings or folds, which are remote on the upper 

 whorls, become more crowded on the penultimate and very 

 numerous on the last whorl; this last whorl is much more 

 inflated than the previous ones, the folds run partly from 

 the infra-sutural tubercles and are either simple or bifurcate 

 or intermediate; the keel is regularly beaded and the basal 

 half is adorned by 9 or 10 beaded spirals, with rather 

 broad interstices , which are radiately ribbed , the ribs 

 uniting the beads of the spirals ; the last whorl has a rather 

 thick yellowish epidermis, with the fine puckerings described 

 by Watson. The umbilicus is quite closed. The aperture 



Notes from the Leyden Museum, Vol. XXV, 



