144 BULLETIN OF THE 



Family VOLUTIDJE. 



This family has submitted to many classifications, and contains several nat- 

 ural groups. Yet, as might be expected when we take into consideration the 

 fossil as well as the recent forms, the lines of demarcation begin to grow less 

 sharp, and characters are interchanged, so that it becomes almost impracticable 

 to distinguish, in the group separated from V. musica, which for present pur- 

 poses we may call Scaphella, features which may serve as a basis for sectional 

 arrangement as opposed to those which possess merely specific value. It 

 would not fall in with the purpose of this paper to discuss the classifications 

 which have been proposed for the entire family, but to pass over the con- 

 dition of those belonging to the fauna of the United States would be equally 

 undesirable. 



The American Volutidce begin in the Cretaceous. The direct progenitor of 

 the recent Scaphella of the east coast of the United States is found in the Eocene 

 (Vicksburg and Red Bluff deposits), and has been described under the name of 

 Caricella demissa by Conrad. It is not a Caricella, but a Valuta, belonging 

 to the group of V. junonia. There is a fine species named V. Newcombiana by 

 Whitfield, in the Eocene of Bells Landing, Alabama, about the middle of the 

 Lignitic series. It recalls V. angulata, and there is no recent species on our 

 coasts which resembles it. Valuta demissa has the tip or nucleus of Aurinia 

 (Eopsephosa Fischer), but strong rounded plaits. The shell is small and 

 thick. The other so-called Volutes of the Eocene seem more closely to ap- 

 proach Volutilithes. In the Miocene there are but two * species of the Scaphella 

 section yet known ; namely, V. Trenholmii T. & H. and V. mutabilis Conrad. 

 The former is exactly like V. demissa in its general features, but has become 

 large and well developed. It persists into the Pliocene ; a variety from the 

 Caloosahatchie Pliocene is intermediate between Trenholmii and the recent 

 junonia. It has been named fioridana by Heilprin. Its descendant is the 

 living junonia of Floridian waters. The V. mutabilis of Conrad was described 

 from the Miocene of Maryland. I have not seen any specimen exactly agreeing 

 with Mr. Conrad's figure. All those specimens labelled Voluta mutabilis which 

 have come under my observation are indistinguishable from S. (Aurinia) dubia 

 of Broderip, still found living in Florida. Some of my specimens are from 

 the original locality. If Mr. Conrad's figure properly represents his type, it 

 is certainly a very strongly marked variety of or possibly distinct from the 

 S. dubia. This group seems to be an offshoot from the demissa-junonia series, 

 and is continued into the Pliocene of South Carolina, where two varieties of 

 dubia are figured by Tuomey and Holmes under the name of mutabilis, though 

 they are possibly not Conrad's mutabilis. In recent seas this line of descent is 

 represented by S. dubia, S. Qouldiana, and S. robusta. 



* V. obtusa Emmons is a young V. mutabilis ; V. solitaria is more of the type of 



Volutilithes. 



February 18, 1889. 



