INSTITUTE OF SCIENCE, PHILADELPHIA. 4II 



This little shell is the precursor of L. gemma of the Newer Miocene and 

 the variety tricarinata Stearns of the Pliocene and recent faunas. From them 

 it differs in its much smaller size and relatively much wider umbilicus. It 

 seems to be very rare in the marl. 



The genus Liotia is represented in the Eocene by L. i^Solariuvi) granulata 

 Lea. As there was a Solarium graimlahiiii of Lamarck, Conrad attempted 

 to rectif)' matters, in 1834, by calling it 5. tricostaticin, and Orbigny, in 1850, 

 proposed for it the name of pseitdogramilatinn. As it is not a Solarium, 

 perhaps we may be permitted to go back to the earliest specific name. The 

 species is not rare at Claiborne, in the horizon of the Claiborne sands, and is 

 also found at Wood's Bluff, Ala. The Solariorbis bella Conrad, referred to 

 Delphimda by De Gregorio, is a mere catalogue name without figure or 

 description. 



The figure of De Gregorio's Delpliimda conscionaria resembles an 

 extremely young yVrt/zVa or jPtf/yz/zirri', too immature for determination. The 

 Delphimda trochiformis and naticoides of H. C. Lea, from the Miocene of 

 Petersburg, Va., are extremely young specimens which have been a good deal 

 worn, and seemed to the writer quite unrecognizable. I have carefully 

 examined the type-specimens which are in the Philadelphia collection. 



Family UMBONIIDyE. 

 Genus UMBONIUM Link. 



There are no species yet reported from our Tertiaries which really belong 

 to this genus as properly defined, yet in the deep waters of the West Indies 

 a recent species is found, so that they may be expected to turn up. The 

 species referred to Adeorbis, Roiella, Umbonium, etc., by Lea and others in the 

 literature, belong to the group about to be discussed. 



In his review of the TrocJddce, Mr. Pilsbry has called attention to the fact 

 that in discussing the genus Etiialia in the Blake Report (p. 359) I had 

 followed Carpenter in characterizing it by the species included under it by 

 Adams, but differing from the two which served as his original types. It is, 

 as Mr. Pilsbry suggests, not unlikely that E. gttamensis may differ from the 

 smaller and more pellucid species which have generally been referred to Ethalia, 

 although, conchologically, the differences are chiefly of size and coloration. 

 At all events, it will be convenient to consider the latter separately. 



Vitrinella having been reserved for the small turbinate hyaline shells with 

 an open umbilicus, large larval shell, and the aperture dilated and sinuated, and 

 Ethalia for the large forms agreeing with E. giiamensis, it remains to allot the 

 several names which have been proposed for the remaining forms, in accord- 

 ance with their characters and the law of priority. 



Teinostoma Adams (P. Z. S., 1853, p. 183) has a depressed shell, with the 

 umbilicus open when young, closed with a large, smooth callus in the adult, 

 and with the aperture drawn away from the axis, expanded and angular or 



