160 PALEONTOLOGY OF NEW JERSEY. 



Genus GLOBICONCHA D'Orb. 



Globiconcha (Tylostoma) curta. 



Plate XIX, Figs. 26, 27. 



Globiconcha curta Gabb : Proc. Acad. Nat. Sci., Phila., 1861, p. 319 ; Meek, Geol. 

 N. J., Newark, 1868, p. 728. 



Mr. Meek cites this as a New Jersey species in his list, given in the 

 Geol. N. J., Newark, 1868, p. 728, but gives no authority for its occurrence. 

 Therefore I must suppose he had himself identified it among New Jersey 

 fossils. The species was originally described from specimens obtained from 

 Comanche Peak, Texas, and is a form which I have not seen represented 

 from localities north of that State. The species is a small globose one, rep- 

 resented ortly by internal casts, and seldom exceeding five-eighths of an inch 

 in extreme length. The specimens are always slightly compressed and are 

 usually marked by a more or less distinct varix on each side of the 

 spire, one of them being on a line with the outer lip of the aperture, showing 

 that they belong to the genus Tylostoma Sharp. The varices are, however, 

 often, and perhaps generally, stronger on one side than on the other. The 

 volutions are about four in number and quite ventricose, the last one forming 

 the greater bulk of the shell. I have not been able to determine if there is 

 any ridge or tooth in the aperture other than that formed by the last varix 

 on the volution, which enters the aperture just above the base of the lip. 

 The examples which I have examined are from Bell County, Texas, and do 

 not show any remains of surface structure ; but the form of the shell is so 

 peculiar that there will be but little risk of mistaking it, should specimens 

 of it be found among the casts from within the State. I have given a figure 

 of the Texas shell for the purpose of aiding in its determination, should it be 

 found, seeing that it has already been given in the State reports as a New 

 Jersey species by so good an authority as Mr. Meek, 



