68 TRANSACTIONS OF THE WAGNER FREE 



of observation in the living Scaphella niagellanica Sby. In some other forms 

 the elevated point is almost or entirely wanting (PL 7, fig. 9) ; these are 

 usually those with large larvae, in which the upper profile is irregularly dome- 

 like and the surface granular or unpolished. The last term of the series, 

 ■ corresponding to Melo in the other line of descent, is furnished by Cymba, in 

 which the nucleus is enormous (PL 7, fig. i), but apparently secondary to a 

 protoconch, though I judge merely from the aspect of very young shells. 

 Since the forms which first show the pointed nucleus (PL 7, fig. 3) were 

 named Caricella by Conrad, I shall refer to that as the Caricella nucletis, the 

 larger and pointless kind may be called the Scapliella micleiis, and the last 

 dome-like form the Cymba nucleus. 



I may observe that, owing to the abominable practice of dealers, who grind 

 and polish every Volute which comes into their possession until the nucleus 

 retains none of its original features, it is almost impossible to tell with accu- 

 racy what sort of nucleus the recent Volutes possess. I have been fortunate 

 in getting a number of specimens which came to me direct from the collector, 

 and from which I have learned more than any one could get from the best 

 museum collections I have seen. The latter are always ground, filed and 

 polished, or acidulated and polished. The collection of the U. S. National 

 Museum has escaped little better than many others. Fossils are often in much 

 more perfect state. No one considers them worth polishing, and they are 

 allowed to remain in a state of nature. I would warn any one who may feel 

 disposed to test the observations of this paper by a study of recent specimens 

 in museums, that they will find it next to impossible, in those forms with small 

 or medium-sized nuclei, to get at the truth at all. 



The original stock from which this type was derived I believe to be the 

 earliest form of Volutilithes or the stock from which the cancellated Volutilithes 

 themselves descended. My reason for this is that in the Tertiary and recent 

 forms (except Cymba) almost without exception the whorls of the adult spire 

 which immediately follow the larval shell exhibit a sculptured or cancellated 

 surface (PL 6, fig. 6, PL 7, figs. 2-5, 8, 9) similar to that of those ancient fossils, 

 and of the two species of recent Volutilithes (PL 6, fig. 4) ; a surface unlike 

 that of any of the true Volutes, which distantly approach it only in Fulgiiraria. 

 This peculiar sculpture must have been very strongly impressed upon the 

 organism, since the character is preserved intact from the beginning of the 

 Eocene down to the recent species, though only on the earliest whorls. It is 

 often eaten off by acid in museum specimens of 5. jtmonia, but in a fresh 

 specimen is beautifully distinct (PL 7, fig. 9). 



I will now tabulate the nucleus forms, with examples of each type in which 

 I have positively ascertained its existence from unmutilated specimens or au- 

 thentic information. 



